The uppercase VulnerabilityAssessmentName returned by the DatabaseVulnerabilityAssessments_CreateOrUpdate API

When creating a [DatabaseVulnerabilityAssessments](https://github.com/Azure/azure-rest-api-specs/blob/0fe46ea84880c3232c7a86db0c73f30975b11b0b/specification/sql/resource-manager/Microsoft.Sql/preview/2021-05-01-preview/DatabaseVulnerabilityAssessments.json#L83) resource. The [value](https://github.com/Azure/azure-rest-api-specs/blob/0fe46ea84880c3232c7a86db0c73f30975b11b0b/specification/sql/resource-manager/Microsoft.Sql/preview/2021-05-01-preview/DatabaseVulnerabilityAssessments.json#L47) of VulnerabilityAssessmentName is fixed as "default" , but the name in response body is "Default". details:

The response body is:
```
{
"properties": {
"storageContainerPath": "https://accsa.blob.core.windows.net/testsc/",
"recurringScans": {
"isEnabled": false,
"emailSubscriptionAdmins": true,
"emails": []
}
},
"id": "/subscriptions/xxx/resourceGroups/testRG-mssql/providers/Microsoft.Sql/servers/testsqlserver/databases/testdb/vulnerabilityAssessments/Default",
"name": "Default",
"type": "Microsoft.Sql/servers/databases/vulnerabilityAssessments"
}
```

Actual: The "name" in response body is "Default". The VulnerabilityAssessmentName of "id" in response body is "Default".
Expected: All VulnerabilityAssessmentName in response body should be "default".

Start with the linked DatabaseVulnerabilityAssessments.json specification, especially the VulnerabilityAssessmentName definition around lines 47 and 83, and compare it with the reported response body. Check whether the specification or the service behavior owns the casing mismatch; done means the documented and returned name and id casing are consistent.

Written by the indexing model from the issue text.