Barman marks Azure Government Blob Endpoint as Emulated

[bdun1013]

Barman only has knowledge of the Azure commercial blob storage endpoint (blob.core.windows.net) and marks all other endpoints as emulated: https://github.com/EnterpriseDB/barman/blob/master/barman/cloud_providers/azure_blob_storage.py#L170

Barman should also support the Azure Government Blob Endpoint (blob.core.usgovcloudapi.net) and not mark it as emulated: https://learn.microsoft.com/en-us/azure/azure-government/compare-azure-government-global-azure