Azure Sql: Wrong capacity when switching from serverless vCore to DTU

**Related command**
`az sql db update`

**Describe the bug**
Updating from a serverless vCore service model with capacity 2 to a DTU model with service objective 3 sets a wrong capacity.

**To Reproduce**
The first cli call sets the db to vCore serverless, the second switches to DTU with implied capacity 100 (service-objective S3) which reveals the bug.
```shell
az sql db update \
--compute-model Serverless \
--capacity 2 \
--edition GeneralPurpose \
--family Gen5 \
--resource-group ResourceGroup \
--server uniform-name \
--name uniform-name \
&& \
az sql db update \
--edition Standard \
--service-objective S3 \
--resource-group ResourceGroup \
--server uniform-name \
--name uniform-name
```

Eventually yields
```json
{
"currentServiceObjectiveName": "S0",
"requestedServiceObjectiveName": "S0",
"sku": {
"capacity": 10,
"family": null,
"name": "Standard",
"size": null,
"tier": "Standard"
}
}
```
The lack of capacity is confirmed by
- matching values in the corresponding web portal view
- the databases' inability to utilize column store idxs

Please see the additional context for the full command output.

**Expected behavior**
The update command should
- scale the database correctly
- yield:
```json
{
"currentServiceObjectiveName": "S3",
"requestedServiceObjectiveName": "S3",
"sku": {
"capacity": 100,
"family": null,
"name": "Standard",
"size": null,
"tier": "Standard"
}
}
```

**Environment summary**
- Ubuntu / apt-get
- Github Actions Ubuntu runner / Azure CLI Action

**Additional context**
Running
```shell
az sql db update \
--edition Standard \
--service-objective S3 \
--resource-group ResourceGroup \
--server uniform-name \
--name uniform-name
```
again sets the capacity correctly.

Full command output:
```json
{
"autoPauseDelay": 60,
"catalogCollation": "SQL_Latin1_General_CP1_CI_AS",
"collation": "SQL_Latin1_General_CP1_CI_AS",
"createMode": null,
"creationDate": "2022-03-15T12:57:22.940000+00:00",
"currentBackupStorageRedundancy": "Local",
"currentServiceObjectiveName": "GP_S_Gen5_2",
"currentSku": {
"capacity": 2,
"family": "Gen5",
"name": "GP_S_Gen5",
"size": null,
"tier": "GeneralPurpose"
},
"databaseId": "some-id",
"defaultSecondaryLocation": "northeurope",
"earliestRestoreDate": "2022-07-11T13:00:42.789103+00:00",
"edition": "GeneralPurpose",
"elasticPoolId": null,
"elasticPoolName": null,
"failoverGroupId": null,
"federatedClientId": null,
"highAvailabilityReplicaCount": null,
"id": "/subscriptions//resourceGroups/ResourceGroup/providers/Microsoft.Sql/servers/uniform-name/databases/uniform-name",
"identity": null,
"isInfraEncryptionEnabled": false,
"kind": "v12.0,user,vcore,serverless",
"ledgerOn": false,
"licenseType": null,
"location": "westeurope",
"longTermRetentionBackupResourceId": null,
"maintenanceConfigurationId": "/subscriptions//providers/Microsoft.Maintenance/publicMaintenanceConfigurations/SQL_Default",
"managedBy": null,
"maxLogSizeBytes": 193273528320,
"maxSizeBytes": 268435456000,
"minCapacity": 0.5,
"name": "uniform-name",
"pausedDate": null,
"primaryDelegatedIdentityClientId": null,
"readScale": "Disabled",
"recoverableDatabaseId": null,
"recoveryServicesRecoveryPointId": null,
"requestedBackupStorageRedundancy": "Local",
"requestedServiceObjectiveName": "GP_S_Gen5_2",
"resourceGroup": "ResourceGroup",
"restorableDroppedDatabaseId": null,
"restorePointInTime": null,
"resumedDate": "2022-07-18T12:36:08.947000+00:00",
"sampleName": null,
"secondaryType": null,
"sku": {
"capacity": 2,
"family": "Gen5",
"name": "GP_S_Gen5",
"size": null,
"tier": "GeneralPurpose"
},
"sourceDatabaseDeletionDate": null,
"sourceDatabaseId": null,
"status": "Online",
"tags": {
"managed-by": "pulumi",
"pulumi-project-name": "some-project",
"stage": "qa"
},
"type": "Microsoft.Sql/servers/databases",
"zoneRedundant": false
}
{
"autoPauseDelay": null,
"catalogCollation": "SQL_Latin1_General_CP1_CI_AS",
"collation": "SQL_Latin1_General_CP1_CI_AS",
"createMode": null,
"creationDate": "2022-03-15T12:57:22.940000+00:00",
"currentBackupStorageRedundancy": "Local",
"currentServiceObjectiveName": "S0",
"currentSku": {
"capacity": 10,
"family": null,
"name": "Standard",
"size": null,
"tier": "Standard"
},
"databaseId": "some-id",
"defaultSecondaryLocation": "northeurope",
"earliestRestoreDate": "2022-07-11T13:02:31.261159+00:00",
"edition": "Standard",
"elasticPoolId": null,
"elasticPoolName": null,
"failoverGroupId": null,
"federatedClientId": null,
"highAvailabilityReplicaCount": null,
"id": "/subscriptions//resourceGroups/ResourceGroup/providers/Microsoft.Sql/servers/uniform-name/databases/uniform-name",
"identity": null,
"isInfraEncryptionEnabled": false,
"kind": "v12.0,user",
"ledgerOn": false,
"licenseType": null,
"location": "westeurope",
"longTermRetentionBackupResourceId": null,
"maintenanceConfigurationId": "/subscriptions//providers/Microsoft.Maintenance/publicMaintenanceConfigurations/SQL_Default",
"managedBy": null,
"maxLogSizeBytes": null,
"maxSizeBytes": 268435456000,
"minCapacity": null,
"name": "uniform-name",
"pausedDate": null,
"primaryDelegatedIdentityClientId": null,
"readScale": "Disabled",
"recoverableDatabaseId": null,
"recoveryServicesRecoveryPointId": null,
"requestedBackupStorageRedundancy": "Local",
"requestedServiceObjectiveName": "S0",
"resourceGroup": "ResourceGroup",
"restorableDroppedDatabaseId": null,
"restorePointInTime": null,
"resumedDate": null,
"sampleName": null,
"secondaryType": null,
"sku": {
"capacity": 10,
"family": null,
"name": "Standard",
"size": null,
"tier": "Standard"
},
"sourceDatabaseDeletionDate": null,
"sourceDatabaseId": null,
"status": "Online",
"tags": {
"managed-by": "pulumi",
"pulumi-project-name": "some-project",
"stage": "qa"
},
"type": "Microsoft.Sql/servers/databases",
"zoneRedundant": false
}
```