Enable the airflow.utils.timezone ban rule

[FrankYang0529]

• airflow.utils.timezone stopped being a real module in Set up process for sharing code between different components. #53149. It added a ruff banned-api rule for it but left it commented out.
• Use common.compat.sdk for timezone imports in providers #70492 cleanup part of timezone imports in providers. This PR handles remaining and enables airflow.utils.timezone ban rule.

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Was generative AI tooling used to co-author this PR?

• Yes - Claude Code

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