Oauth/OIDC Azure IMDS metadata based authentication for Schema Registry

[emasab]

What

Implement metadata based authentication with Azure IMDS returning an OAuth/OIDC token. Implementation is for both the synchronous and asynchronous client. Before implementing the feature did a refactor to make it more maintainable to add new authentication methods.

Checklist

• [ ] Contains customer facing changes? Including API/behavior changes
• [x] Unit tests are present, similar to those present to OAuth/OIDC with client_credentials

References

JIRA:

Test & Review

Run the normal test suite. An example in present for how to use the SR authentication methods and the Kafka one as well.

Open questions / Follow-ups