Add-AzIoTDeviceProvisioningServiceLinkedHub allows creation of duplicate links

## Description
Using the Add-AzIoTDeviceProvisioningServiceLinkedHub cmdlet, it is possible to create the same link twice. These are both visible within the Azure Portal and via Powershell. Trying to create a third identical link throws a `bad request` error.

View in the Azure Portal:
https://i.imgur.com/Fj4z5fg.png

Selecting either one of these Links within the Portal and then clicking Delete removes both Links.

## Steps to reproduce

```powershell
# First Creation
$linkParams = @{
ResourceGroupName = $dpsResourceGroup
Name = $dpsName
IotHubConnectionString = $iotHubConn
IotHubLocation = $resourceGroupLocation
}
Add-AzIoTDeviceProvisioningServiceLinkedHub @linkParams

# First Output
# ResourceGroupName : As above
# Name : As above
# LinkedHubName : xxxx.azure-devices.net
# ConnectionString : As Above
# AllocationWeight :
# ApplyAllocationPolicy : False
# Location : westeurope

# Second Creation
$linkParams = @{
ResourceGroupName = $dpsResourceGroup
Name = $dpsName
IotHubConnectionString = $iotHubConn
IotHubLocation = $resourceGroupLocation
}
Add-AzIoTDeviceProvisioningServiceLinkedHub @linkParams

# Second Output
# LinkedHubName Location AllocationWeight ApplyAllocationPolicy
# ------------- -------- ---------------- ---------------------
# xxxx.azure-devices.net westeurope False
# xxxx.azure-devices.net westeurope False

# Third Creation
$linkParams = @{
ResourceGroupName = $dpsResourceGroup
Name = $dpsName
IotHubConnectionString = $iotHubConn
IotHubLocation = $resourceGroupLocation
}
Add-AzIoTDeviceProvisioningServiceLinkedHub @linkParams

# Third Output
# Add-AzIoTDeviceProvisioningServiceLinkedHub : Operation returned an invalid status code 'BadRequest'
# At line:7 char:1
# + Add-AzIoTDeviceProvisioningServiceLinkedHub @linkParams
# + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# + CategoryInfo : CloseError: (:) [Add-AzIoTDevice...erviceLinkedHub], ErrorDetailsException
# + FullyQualifiedErrorId : Microsoft.Azure.Commands.Management.DeviceProvisioningServices.AddAzureRmIotDeviceProvisioningServiceLinkedHub
```

## Environment data

```
Name Value
---- -----
PSVersion 5.1.18362.145
PSEdition Desktop
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0...}
BuildVersion 10.0.18362.145
CLRVersion 4.0.30319.42000
WSManStackVersion 3.0
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1
```

## Module versions

```powershell

Directory: C:\Users\xxxx\Documents\WindowsPowerShell\Modules

ModuleType Version Name ExportedCommands
---------- ------- ---- ----------------
Script 1.6.3 Az.Accounts {Disable-AzDataCollection, Disable-AzContextAutosave, Enable-AzDataColle...
Script 1.0.1 Az.Advisor {Get-AzAdvisorRecommendation, Enable-AzAdvisorRecommendation, Disable-Az...
Script 1.0.2 Az.Aks {Get-AzAks, New-AzAks, Remove-AzAks, Import-AzAksCredential...}
Script 1.1.1 Az.AnalysisServices {Resume-AzAnalysisServicesServer, Suspend-AzAnalysisServicesServer, Get-...
Script 1.3.2 Az.ApiManagement {Add-AzApiManagementApiToProduct, Add-AzApiManagementProductToGroup, Add...
Script 1.0.2 Az.ApplicationInsights {Get-AzApplicationInsights, New-AzApplicationInsights, Remove-AzApplicat...
Script 1.3.4 Az.Automation {Get-AzAutomationHybridWorkerGroup, Remove-AzAutomationHybridWorkerGroup...
Script 1.1.2 Az.Batch {Remove-AzBatchAccount, Get-AzBatchAccount, Get-AzBatchAccountKey, New-A...
Script 1.0.1 Az.Billing {Get-AzBillingInvoice, Get-AzBillingPeriod, Get-AzEnrollmentAccount, Get...
Script 1.3.1 Az.Cdn {Get-AzCdnProfile, Get-AzCdnProfileSsoUrl, New-AzCdnProfile, Remove-AzCd...
Script 1.2.1 Az.CognitiveServices {Get-AzCognitiveServicesAccount, Get-AzCognitiveServicesAccountKey, Get-...
Script 2.7.0 Az.Compute {Remove-AzAvailabilitySet, Get-AzAvailabilitySet, New-AzAvailabilitySet,...
Script 1.0.1 Az.ContainerInstance {New-AzContainerGroup, Get-AzContainerGroup, Remove-AzContainerGroup, Ge...
Script 1.1.0 Az.ContainerRegistry {New-AzContainerRegistry, Get-AzContainerRegistry, Update-AzContainerReg...
Script 1.4.0 Az.DataFactory {Set-AzDataFactoryV2, Update-AzDataFactoryV2, Get-AzDataFactoryV2, Remov...
Script 1.0.1 Az.DataLakeAnalytics {Get-AzDataLakeAnalyticsDataSource, New-AzDataLakeAnalyticsCatalogCreden...
Script 1.2.3 Az.DataLakeStore {Get-AzDataLakeStoreTrustedIdProvider, Remove-AzDataLakeStoreTrustedIdPr...
Script 1.0.1 Az.DeploymentManager {Get-AzDeploymentManagerArtifactSource, New-AzDeploymentManagerArtifactS...
Script 1.0.0 Az.DevTestLabs {Get-AzDtlAllowedVMSizesPolicy, Get-AzDtlAutoShutdownPolicy, Get-AzDtlAu...
Script 1.1.1 Az.Dns {Get-AzDnsRecordSet, New-AzDnsRecordConfig, Remove-AzDnsRecordSet, Set-A...
Script 1.2.2 Az.EventGrid {New-AzEventGridTopic, Get-AzEventGridTopic, Set-AzEventGridTopic, New-A...
Script 1.4.0 Az.EventHub {New-AzEventHubNamespace, Get-AzEventHubNamespace, Set-AzEventHubNamespa...
Script 1.1.1 Az.FrontDoor {New-AzFrontDoor, Get-AzFrontDoor, Set-AzFrontDoor, Remove-AzFrontDoor...}
Script 2.0.2 Az.HDInsight {Get-AzHDInsightJob, New-AzHDInsightSqoopJobDefinition, Wait-AzHDInsight...
Script 1.0.0 Az.HealthcareApis {New-AzHealthcareApisService, Remove-AzHealthcareApisService, Set-AzHeal...
Script 1.3.1 Az.IotHub {Add-AzIotHubKey, Get-AzIotHubEventHubConsumerGroup, Get-AzIotHubConnect...
Script 1.3.1 Az.KeyVault {Add-AzKeyVaultCertificate, Update-AzKeyVaultCertificate, Stop-AzKeyVaul...
Script 1.3.1 Az.LogicApp {Get-AzIntegrationAccountAgreement, Get-AzIntegrationAccountAssembly, Ge...
Script 1.1.1 Az.MachineLearning {Move-AzMlCommitmentAssociation, Get-AzMlCommitmentAssociation, Get-AzMl...
Script 1.0.1 Az.ManagedServices {Get-AzManagedServicesAssignment, New-AzManagedServicesAssignment, Remov...
Script 1.0.1 Az.MarketplaceOrdering {Get-AzMarketplaceTerms, Set-AzMarketplaceTerms}
Script 1.1.0 Az.Media {Sync-AzMediaServiceStorageKey, Set-AzMediaServiceKey, Get-AzMediaServic...
Script 1.4.0 Az.Monitor {Get-AzMetricDefinition, Get-AzMetric, Remove-AzLogProfile, Get-AzLogPro...
Script 1.15.0 Az.Network {Add-AzApplicationGatewayAuthenticationCertificate, Get-AzApplicationGat...
Script 1.1.0 Az.NotificationHubs {Get-AzNotificationHub, Get-AzNotificationHubAuthorizationRule, Get-AzNo...
Script 1.3.3 Az.OperationalInsights {New-AzOperationalInsightsAzureActivityLogDataSource, New-AzOperationalI...
Script 1.1.3 Az.PolicyInsights {Get-AzPolicyEvent, Get-AzPolicyState, Get-AzPolicyStateSummary, Get-AzP...
Script 1.1.0 Az.PowerBIEmbedded {Remove-AzPowerBIWorkspaceCollection, Get-AzPowerBIWorkspaceCollection, ...
Script 1.4.5 Az.RecoveryServices {Get-AzRecoveryServicesBackupProperty, Get-AzRecoveryServicesVault, Get-...
Script 1.1.1 Az.RedisCache {Remove-AzRedisCachePatchSchedule, New-AzRedisCacheScheduleEntry, Get-Az...
Script 1.0.2 Az.Relay {New-AzRelayNamespace, Get-AzRelayNamespace, Set-AzRelayNamespace, Remov...
Script 1.7.0 Az.Resources {Get-AzProviderOperation, Remove-AzRoleAssignment, Get-AzRoleAssignment,...
Script 1.4.0 Az.ServiceBus {New-AzServiceBusNamespace, Get-AzServiceBusNamespace, Set-AzServiceBusN...
Script 1.2.0 Az.ServiceFabric {Add-AzServiceFabricApplicationCertificate, Add-AzServiceFabricClientCer...
Script 1.1.0 Az.SignalR {New-AzSignalR, Get-AzSignalR, Get-AzSignalRKey, New-AzSignalRKey...}
Script 1.15.0 Az.Sql {Get-AzSqlDatabaseTransparentDataEncryption, Get-AzSqlDatabaseTransparen...
Script 1.8.0 Az.Storage {Get-AzStorageAccount, Get-AzStorageAccountKey, New-AzStorageAccount, Ne...
Script 1.2.1 Az.StorageSync {Invoke-AzStorageSyncCompatibilityCheck, New-AzStorageSyncService, Get-A...
Script 1.0.0 Az.StreamAnalytics {Get-AzStreamAnalyticsFunction, Get-AzStreamAnalyticsDefaultFunctionDefi...
Script 1.0.2 Az.TrafficManager {Add-AzTrafficManagerCustomHeaderToEndpoint, Remove-AzTrafficManagerCust...
Script 1.5.0 Az.Websites {Get-AzAppServicePlan, Set-AzAppServicePlan, New-AzAppServicePlan, Remov...

Directory: C:\Program Files\WindowsPowerShell\Modules

ModuleType Version Name ExportedCommands
---------- ------- ---- ----------------
Script 1.6.4 Az.Accounts {Disable-AzDataCollection, Disable-AzContextAutosave, Enable-AzDataColle...
Script 1.1.0 Az.Advisor {Get-AzAdvisorRecommendation, Enable-AzAdvisorRecommendation, Disable-Az...
Script 2.0.1 Az.Batch {Remove-AzBatchAccount, Get-AzBatchAccount, Get-AzBatchAccountKey, New-A...
Script 1.4.0 Az.Cdn {Get-AzCdnProfile, Get-AzCdnProfileSsoUrl, New-AzCdnProfile, Remove-AzCd...
Script 3.0.0 Az.Compute {Remove-AzAvailabilitySet, Get-AzAvailabilitySet, New-AzAvailabilitySet,...
Script 1.4.1 Az.DataFactory {Set-AzDataFactoryV2, Update-AzDataFactoryV2, Get-AzDataFactoryV2, Remov...
Script 1.2.4 Az.DataLakeStore {Get-AzDataLakeStoreTrustedIdProvider, Remove-AzDataLakeStoreTrustedIdPr...
Script 0.7.1 Az.DeviceProvisioningServices {New-AzIoTDeviceProvisioningService, Get-AzIoTDeviceProvisioningService,...
Script 1.1.2 Az.FrontDoor {New-AzFrontDoor, Get-AzFrontDoor, Set-AzFrontDoor, Remove-AzFrontDoor...}
Script 3.0.0 Az.HDInsight {Get-AzHDInsightJob, New-AzHDInsightSqoopJobDefinition, Wait-AzHDInsight...
Script 2.0.0 Az.IotHub {Add-AzIotHubKey, Get-AzIotHubEventHubConsumerGroup, Get-AzIotHubConnect...
Script 2.0.0 Az.Network {Add-AzApplicationGatewayAuthenticationCertificate, Get-AzApplicationGat...
Script 1.0.0 Az.PrivateDns {Get-AzPrivateDnsZone, Remove-AzPrivateDnsZone, Set-AzPrivateDnsZone, Ne...
Script 2.0.1 Az.RecoveryServices {Get-AzRecoveryServicesBackupProperty, Get-AzRecoveryServicesVault, Get-...
Script 1.7.1 Az.Resources {Get-AzProviderOperation, Remove-AzRoleAssignment, Get-AzRoleAssignment,...
Script 2.0.0 Az.ServiceFabric {Add-AzServiceFabricClientCertificate, Add-AzServiceFabricClusterCertifi...
Script 2.0.0 Az.Sql {Get-AzSqlDatabaseTransparentDataEncryption, Get-AzSqlDatabaseTransparen...
Script 1.9.0 Az.Storage {Get-AzStorageAccount, Get-AzStorageAccountKey, New-AzStorageAccount, Ne...
Script 5.3.0 Azure {Get-AzureAutomationCertificate, Get-AzureAutomationConnection, New-Azur...
Script 4.6.1 Azure.Storage {Get-AzureStorageTable, New-AzureStorageTableSASToken, New-AzureStorageT...
Binary 2.0.2.52 AzureAD {Add-AzureADApplicationOwner, Get-AzureADApplication, Get-AzureADApplica...
Binary 2.0.2.62 AzureADPreview {Add-AzureADApplicationOwner, Get-AzureADApplication, Get-AzureADApplica...
Script 1.0.0.5 AzureIoT {Connect-AzureIoTHub, Get-IoTCloudClient, Get-IoTDeviceClient, Get-IotDe...
Script 5.8.3 AzureRM.profile {Disable-AzureRmDataCollection, Disable-AzureRmContextAutosave, Enable-A...
Script 1.0.1 Microsoft.PowerShell.Operation.V... {Get-OperationValidation, Invoke-OperationValidation}
Binary 1.0.0.1 PackageManagement {Find-Package, Get-Package, Get-PackageProvider, Get-PackageSource...}
Script 3.4.0 Pester {Describe, Context, It, Should...}
Manifest 2.2 Posh-SSH {Get-SCPFile, Get-SCPFolder, Get-SCPItem, Get-SFTPFile...}
Script 1.0.0.1 PowerShellGet {Install-Module, Find-Module, Save-Module, Update-Module...}
Script 2.0.0 PSReadline {Get-PSReadLineKeyHandler, Set-PSReadLineKeyHandler, Remove-PSReadLineKe...

Directory: C:\WINDOWS\system32\WindowsPowerShell\v1.0\Modules

ModuleType Version Name ExportedCommands
---------- ------- ---- ----------------
Manifest 1.0.0.0 AppBackgroundTask {Disable-AppBackgroundTaskDiagnosticLog, Enable-AppBackgroundTaskDiagnos...
Manifest 2.0.0.0 AppLocker {Get-AppLockerFileInformation, Get-AppLockerPolicy, New-AppLockerPolicy,...
Manifest 1.0.0.0 AppvClient {Add-AppvClientConnectionGroup, Add-AppvClientPackage, Add-AppvPublishin...
Manifest 2.0.1.0 Appx {Add-AppxPackage, Get-AppxPackage, Get-AppxPackageManifest, Remove-AppxP...
Script 1.0.0.0 AssignedAccess {Clear-AssignedAccess, Get-AssignedAccess, Set-AssignedAccess}
Manifest 1.0.0.0 BitLocker {Unlock-BitLocker, Suspend-BitLocker, Resume-BitLocker, Remove-BitLocker...
Manifest 2.0.0.0 BitsTransfer {Add-BitsFile, Complete-BitsTransfer, Get-BitsTransfer, Remove-BitsTrans...
Manifest 1.0.0.0 BranchCache {Add-BCDataCacheExtension, Clear-BCCache, Disable-BC, Disable-BCDowngrad...
Manifest 1.0.0.0 CimCmdlets {Get-CimAssociatedInstance, Get-CimClass, Get-CimInstance, Get-CimSessio...
Manifest 1.0 ConfigCI {Get-SystemDriver, New-CIPolicyRule, New-CIPolicy, Get-CIPolicy...}
Manifest 1.0 ConfigDefender {Get-MpPreference, Set-MpPreference, Add-MpPreference, Remove-MpPreferen...
Manifest 1.0 Defender {Get-MpPreference, Set-MpPreference, Add-MpPreference, Remove-MpPreferen...
Manifest 1.0.2.0 DeliveryOptimization {Delete-DeliveryOptimizationCache, Get-DeliveryOptimizationStatus, Set-D...
Manifest 1.0.0.0 DirectAccessClientComponents {Disable-DAManualEntryPointSelection, Enable-DAManualEntryPointSelection...
Script 3.0 Dism {Add-AppxProvisionedPackage, Add-WindowsDriver, Add-WindowsCapability, A...
Manifest 1.0.0.0 DnsClient {Resolve-DnsName, Clear-DnsClientCache, Get-DnsClient, Get-DnsClientCach...
Manifest 1.0.0.0 EventTracingManagement {Start-EtwTraceSession, New-EtwTraceSession, Get-EtwTraceSession, Update...
Manifest 1.0.0.0 HgsClient {Get-HgsAttestationBaselinePolicy, Get-HgsClientConfiguration, Test-HgsC...
Manifest 1.0.0.0 HgsDiagnostics {New-HgsTraceTarget, Get-HgsTrace, Get-HgsTraceFileData, Test-HgsTraceTa...
Manifest 1.0.0.1 HostNetworkingService {Remove-HnsNamespace, Remove-HnsEndpoint, Get-HnsEndpoint, Get-HnsNamesp...
Binary 2.0.0.0 Hyper-V {Add-VMAssignableDevice, Add-VMDvdDrive, Add-VMFibreChannelHba, Add-VMGp...
Binary 1.1 Hyper-V {Add-VMDvdDrive, Add-VMFibreChannelHba, Add-VMHardDiskDrive, Add-VMMigra...
Manifest 2.0.0.0 International {Get-WinDefaultInputMethodOverride, Set-WinDefaultInputMethodOverride, G...
Manifest 1.0.0.0 iSCSI {Get-IscsiTargetPortal, New-IscsiTargetPortal, Remove-IscsiTargetPortal,...
Script 1.0.0.0 ISE {New-IseSnippet, Import-IseSnippet, Get-IseSnippet}
Manifest 1.0.0.0 Kds {Add-KdsRootKey, Get-KdsRootKey, Test-KdsRootKey, Set-KdsConfiguration...}
Manifest 1.0.1.0 Microsoft.PowerShell.Archive {Compress-Archive, Expand-Archive}
Manifest 3.0.0.0 Microsoft.PowerShell.Diagnostics {Get-WinEvent, Get-Counter, Import-Counter, Export-Counter...}
Manifest 3.0.0.0 Microsoft.PowerShell.Host {Start-Transcript, Stop-Transcript}
Manifest 1.0.0.0 Microsoft.PowerShell.LocalAccounts {Add-LocalGroupMember, Disable-LocalUser, Enable-LocalUser, Get-LocalGro...
Manifest 3.1.0.0 Microsoft.PowerShell.Management {Add-Content, Clear-Content, Clear-ItemProperty, Join-Path...}
Script 1.0 Microsoft.PowerShell.ODataUtils Export-ODataEndpointProxy
Manifest 3.0.0.0 Microsoft.PowerShell.Security {Get-Acl, Set-Acl, Get-PfxCertificate, Get-Credential...}
Manifest 3.1.0.0 Microsoft.PowerShell.Utility {Format-List, Format-Custom, Format-Table, Format-Wide...}
Manifest 3.0.0.0 Microsoft.WSMan.Management {Disable-WSManCredSSP, Enable-WSManCredSSP, Get-WSManCredSSP, Set-WSManQ...
Manifest 1.0 MMAgent {Disable-MMAgent, Enable-MMAgent, Set-MMAgent, Get-MMAgent...}
Manifest 1.0.0.0 MsDtc {New-DtcDiagnosticTransaction, Complete-DtcDiagnosticTransaction, Join-D...
Manifest 2.0.0.0 NetAdapter {Disable-NetAdapter, Disable-NetAdapterBinding, Disable-NetAdapterChecks...
Manifest 1.0.0.0 NetConnection {Get-NetConnectionProfile, Set-NetConnectionProfile}
Manifest 1.0.0.0 NetEventPacketCapture {New-NetEventSession, Remove-NetEventSession, Get-NetEventSession, Set-N...
Manifest 2.0.0.0 NetLbfo {Add-NetLbfoTeamMember, Add-NetLbfoTeamNic, Get-NetLbfoTeam, Get-NetLbfo...
Manifest 1.0.0.0 NetNat {Get-NetNat, Get-NetNatExternalAddress, Get-NetNatStaticMapping, Get-Net...
Manifest 2.0.0.0 NetQos {Get-NetQosPolicy, Set-NetQosPolicy, Remove-NetQosPolicy, New-NetQosPolicy}
Manifest 2.0.0.0 NetSecurity {Get-DAPolicyChange, New-NetIPsecAuthProposal, New-NetIPsecMainModeCrypt...
Manifest 1.0.0.0 NetSwitchTeam {New-NetSwitchTeam, Remove-NetSwitchTeam, Get-NetSwitchTeam, Rename-NetS...
Manifest 1.0.0.0 NetTCPIP {Get-NetIPAddress, Get-NetIPInterface, Get-NetIPv4Protocol, Get-NetIPv6P...
Manifest 1.0.0.0 NetworkConnectivityStatus {Get-DAConnectionStatus, Get-NCSIPolicyConfiguration, Reset-NCSIPolicyCo...
Manifest 1.0.0.0 NetworkSwitchManager {Disable-NetworkSwitchEthernetPort, Enable-NetworkSwitchEthernetPort, Ge...
Manifest 1.0.0.0 NetworkTransition {Add-NetIPHttpsCertBinding, Disable-NetDnsTransitionConfiguration, Disab...
Manifest 1.0.0.0 PcsvDevice {Get-PcsvDevice, Start-PcsvDevice, Stop-PcsvDevice, Restart-PcsvDevice...}
Binary 1.0.0.0 PersistentMemory {Get-PmemDisk, Get-PmemPhysicalDevice, Get-PmemUnusedRegion, New-PmemDis...
Manifest 1.0.0.0 PKI {Add-CertificateEnrollmentPolicyServer, Export-Certificate, Export-PfxCe...
Manifest 1.0.0.0 PnpDevice {Get-PnpDevice, Get-PnpDeviceProperty, Enable-PnpDevice, Disable-PnpDevice}
Manifest 1.1 PrintManagement {Add-Printer, Add-PrinterDriver, Add-PrinterPort, Get-PrintConfiguration...
Binary 1.0.11 ProcessMitigations {Get-ProcessMitigation, Set-ProcessMitigation, ConvertTo-ProcessMitigati...
Script 3.0 Provisioning {Install-ProvisioningPackage, Export-ProvisioningPackage, Install-Truste...
Manifest 1.1 PSDesiredStateConfiguration {Set-DscLocalConfigurationManager, Start-DscConfiguration, Test-DscConfi...
Script 1.0.0.0 PSDiagnostics {Disable-PSTrace, Disable-PSWSManCombinedTrace, Disable-WSManTrace, Enab...
Binary 1.1.0.0 PSScheduledJob {New-JobTrigger, Add-JobTrigger, Remove-JobTrigger, Get-JobTrigger...}
Manifest 2.0.0.0 PSWorkflow {New-PSWorkflowExecutionOption, New-PSWorkflowSession, nwsn}
Manifest 1.0.0.0 PSWorkflowUtility Invoke-AsWorkflow
Manifest 1.0.0.0 ScheduledTasks {Get-ScheduledTask, Set-ScheduledTask, Register-ScheduledTask, Unregiste...
Manifest 2.0.0.0 SecureBoot {Confirm-SecureBootUEFI, Set-SecureBootUEFI, Get-SecureBootUEFI, Format-...
Manifest 2.0.0.0 SmbShare {Get-SmbShare, Remove-SmbShare, Set-SmbShare, Block-SmbShareAccess...}
Manifest 2.0.0.0 SmbWitness {Get-SmbWitnessClient, Move-SmbWitnessClient, gsmbw, msmbw...}
Manifest 1.0.0.0 StartLayout {Export-StartLayout, Import-StartLayout, Export-StartLayoutEdgeAssets, G...
Manifest 2.0.0.0 Storage {Add-InitiatorIdToMaskingSet, Add-PartitionAccessPath, Add-PhysicalDisk,...
Manifest 1.0.0.0 StorageBusCache {Clear-StorageBusDisk, Disable-StorageBusCache, Disable-StorageBusDisk, ...
Manifest 2.0.0.0 TLS {New-TlsSessionTicketKey, Enable-TlsSessionTicketKey, Disable-TlsSession...
Manifest 1.0.0.0 TroubleshootingPack {Get-TroubleshootingPack, Invoke-TroubleshootingPack}
Manifest 2.0.0.0 TrustedPlatformModule {Get-Tpm, Initialize-Tpm, Clear-Tpm, Unblock-Tpm...}
Binary 2.1.639.0 UEV {Clear-UevConfiguration, Clear-UevAppxPackage, Restore-UevBackup, Set-Ue...
Manifest 2.0.0.0 VpnClient {Add-VpnConnection, Set-VpnConnection, Remove-VpnConnection, Get-VpnConn...
Manifest 1.0.0.0 Wdac {Get-OdbcDriver, Set-OdbcDriver, Get-OdbcDsn, Add-OdbcDsn...}
Manifest 2.0.0.0 Whea {Get-WheaMemoryPolicy, Set-WheaMemoryPolicy}
Manifest 1.0.0.0 WindowsDeveloperLicense {Get-WindowsDeveloperLicense, Unregister-WindowsDeveloperLicense, Show-W...
Script 1.0 WindowsErrorReporting {Enable-WindowsErrorReporting, Disable-WindowsErrorReporting, Get-Window...
Manifest 1.0.0.0 WindowsSearch {Get-WindowsSearchSetting, Set-WindowsSearchSetting}
Manifest 1.0.0.0 WindowsUpdate Get-WindowsUpdateLog
Manifest 1.0.0.2 WindowsUpdateProvider {Get-WUAVersion, Get-WULastInstallationDate, Get-WULastScanSuccessDate, ...

Directory: C:\Program Files (x86)\Microsoft SQL Server\140\Tools\PowerShell\Modules

ModuleType Version Name ExportedCommands
---------- ------- ---- ----------------
Manifest 14.0 SQLPS {Backup-SqlDatabase, Save-SqlMigrationReport, Add-SqlAvailabilityDatabas...

```

## Debug output

```

```

## Error output

```

```

Start by reproducing the duplicate-link behavior with Add-AzIoTDeviceProvisioningServiceLinkedHub using the PowerShell commands in the issue. Trace that cmdlet's implementation and its existing tests, if present, to determine how linked hubs are created and reported. Done means repeated identical requests no longer create duplicate links while the command's behavior for a third request is defined and verified.

Written by the indexing model from the issue text.