Update requirements-schemaregistry.txt - authlib min version

[yairm210]

What

Recent changes have added an authlib dependency to schema registry code - specifically, from authlib.integrations.httpx_client import OAuth2Client

This is code that does not exist in older authlib versions (added here) and thus will break on import, if confluent_kafka is added to a repo which already contains an older version of authlib, since it "satisfies the dependency".
Theoretically one can use authlib >= 0.13.0, but since the next couple of versions are all "fix httpx", the first version I would trust to not break compatibility with what you tested would be version 1.0.0.

Checklist

• Contains customer facing changes? Including API/behavior changes
• Did you add sufficient unit test and/or integration test coverage for this PR?
  • Tested the min version, this adds no new code

References

Test & Review

Tested both import and usage with 1.0.0, works fine

[confluent-cla-assistant]

🎉 All Contributor License Agreements have been signed. Ready to merge.
✅ yairm210
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[rayokota]

/sem-approve