Add azureusgovernment to environment list, fix Makefile

[rguptar]

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1. The Azure CLI az cloud list -o table and the various Azure SDKs refer to govcloud as AzureUSGovernment. This PR adds support for that name. This broke our deployment when using the Azure Key Vault Provider for Secrets Store CSI Driver.
2. Minor fixes were made to the Makefile so it works out of the box. It was also renamed.

[jhendrixMSFT]

I'm unclear on why this is now a problem. The naming has been like this for years. Can you please clarify?

[rguptar]

The other Azure SDKs refer to govcloud as AzureUSGovernment. Some examples
JS: https://github.com/Azure/azure-sdk-for-node/blob/44c0332f9f6515e1b442c6867a8bcad98c1b3ae9/lib/azure.js#L3101
.NET: https://github.com/Azure/azure-sdk-for-net/blob/4a5228748e048c3fb98a2b91a9c3473c2590fa51/sdk/identity/Azure.Identity/src/Credentials/VisualStudioCodeCredential.cs#L179
Python: https://github.com/Azure/azure-sdk-for-python/blob/01ab6a108c0e8d719b5239f06118454a9e7dc0c0/sdk/identity/azure-identity/azure/identity/_credentials/vscode.py#L87
Ruby: https://github.com/Azure/azure-sdk-for-ruby/blob/9175ace5230a9b63be963ebf4cb4ee42e08f8804/runtime/ms_rest_azure/lib/ms_rest_azure/azure_environment.rb#L124

A customer would likely refer to az cloud list to get the cloud name and this shows AzureUSGovernment.

[jhendrixMSFT]

Fixes #624