SqlSetup: FailoverCluster feature doesn't support network share as storage

Details of the scenario you tried and the problem that is occurring
Currently the FCI setup only supports using shared volumes. However, SQL Server FCI can also use a network share instead of shared volumes. This scenario needs to be added to the module.

Verbose logs showing the problem
VERBOSE: [SQLFSX1]: LCM: [ End Set ] [[SqlSetup]InstallFCINode1] in 6.6640 seconds.
PowerShell DSC resource DSC_SqlSetup failed to execute Set-TargetResource functionality with error message: System.Exception: Unable to map the specified paths to valid cluster storage. Drives mapped: .
+ CategoryInfo : InvalidOperation: (:) [], CimException
+ FullyQualifiedErrorId : ProviderOperationExecutionFailure
+ PSComputerName : localhost

Suggested solution to the issue
Add the option to not use any shared volumes, and instead simply provide network share UNC for MSSQL directories.

The DSC configuration that is used to reproduce the issue (as detailed as possible)

insert configuration here

SQL Server edition and version the target node is running
MSSQL 2019, Developer Edition

SQL Server PowerShell modules present on the target node
None

The operating system the target node is running
OsName : Microsoft Windows Server 2019 Datacenter
OsOperatingSystemSKU : DatacenterServerEdition
OsArchitecture : 64-bit
WindowsVersion : 1809
WindowsBuildLabEx : 17763.1.amd64fre.rs5_release.180914-1434
OsLanguage : en-US
OsMuiLanguages : {en-US}

Version and build of PowerShell the target node is running
Name Value

PSVersion 5.1.17763.1490
PSEdition Desktop
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0...}
BuildVersion 10.0.17763.1490
CLRVersion 4.0.30319.42000
WSManStackVersion 3.0
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1

Version of the DSC module that was used
Name Version Path

SqlServerDsc 14.2.1 C:\Program Files\WindowsPowerShell\Modules\SqlServerDsc\14.2.1\SqlServerDsc.psd1

Review the SqlSetup FailoverCluster/FCI setup path described in the issue and trace where valid cluster storage is required. Reproduce the reported network-share scenario on the stated SQL Server 2019 and Windows Server 2019 environment, then verify that an FCI configuration using UNC paths without shared volumes completes successfully.