[ACR] [Before GA] Update cloud configuration API

[annelo-msft]

Once the service team has added data plane scopes, we will update our authentication_scope kwarg as follows:

• Remove authentication_scope kwarg
• Add audience (or similarly named) kwarg
• audience is an extensible enum, containing the audience strings for known clouds; the user can override with a string if needed
• If audience is set, client library will append /.default to audience value to specify the default scope
• audience will default to data-plane scope root, which should be common across clouds [Note: this is not yet available from the service]
• Throw an exception is audience is not set and update samples to reflect this

In Python, we will also

• Initially not support credential_scopes kwarg
• If we do evenually support the credential_scopes kwarg, raise an error if this is different from the scope determined from audience

Please see Azure/azure-sdk-for-net#21603 for further details.

[annelo-msft]

@johanste @lmazuel @schaabs FYI

[YalinLi0312]

Fixed.