Implement ACR API Updates

[annelo-msft]

We're making some design changes per arch board feedback. Once these are complete, we'll need to implement these changes for all four languages.

This will include:

• Re-generating code from the updated swagger file
• Moving methods to repository and artifact helper classes
• Implementing the lazy digest lookup in RegistryArtifact
• Updating tests and samples

[jeremymeng]

PR #15109