Data Share Account will return all keys of tags in lowercase

If I create a data share account with tags. It will always return the keys of tags in lowercase.

PUT https://management.azure.com/subscriptions/{{subscriptionId}}/resourceGroups/yupserver/providers/Microsoft.DataShare/accounts/yup?api-version=2019-11-01
{
"location": "West US 2",
"tags": {
"Env": "Test"
},
"identity": {
"type": "SystemAssigned"
}

}

Response:
{
"identity": {
"type": "SystemAssigned",
"principalId": "xx-xx",
"tenantId": "xx-xx"
},
"properties": {
"createdAt": "2020-04-30T02:33:16.2470547Z",
"provisioningState": "Creating",
"userName": "azure-cli-2019-10-16-07-33-33",
"userEmail": ""
},
"id": "/subscriptions/85b3dbca-5974-4067-9669-67a141095a76/resourceGroups/yupserver/providers/Microsoft.DataShare/accounts/yup",
"name": "yup",
"type": "Microsoft.DataShare/accounts",
"location": "westus2",
"tags": {
"env": "Test2"
}
}

Start with the Azure Data Share accounts API request and response shown in the issue, including the 2019-11-01 endpoint and tags object. Compare the documented contract with the observed lowercase key behavior and verify the expected casing; done means the specification clearly reflects the intended tag-key behavior.

Written by the indexing model from the issue text.