azure-schemaregistry needs linting updates for pylint version 3.2.7

[azure-sdk]

ACTION NEEDED: This version of pylint will be merged on 2025-04-14. The build will begin to fail for this library if errors are not fixed.

Library name: azure-schemaregistry
Pylint version: 3.2.7
Pylint errors: Link to build (2025-02-16)
How to fix: Run the next-pylint tox command at the library package-level and resolve the linting errors.

1. ../azure-schemaregistry>pip install "tox<5"
2. ../azure-schemaregistry>tox run -e next-pylint -c ../../../eng/tox/tox.ini --root .

See the Pylint Guide for more information.