Support managed identity, Key Vault managed keys

[asears]

Is your feature request related to a problem? Please describe.

Security feature request

Describe the solution you'd like

Provide support for managed identity / other methods of secure authentication to the service besides API Key. Manage key rotations with Key Vault to remove any need to rotate keys manually or via scripts. and provide samples when working with the secret portions of the code.

See https://docs.microsoft.com/en-us/azure/key-vault/secrets/overview-storage-keys

Additional context

Add any other context or screenshots about the feature request here.