Breeze: keep OpenAPI Generator version in sync during CI upgrades

[anishgirianish]

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Integrates OpenAPI Generator version updates into the existing Breeze CI upgrade flow, addressing the maintenance gap described in #59229. This ensures the pinned generator version is automatically kept in sync when running standard upgrade tooling, without changing generated clients or runtime behavior.

closes: #59229

^ Add meaningful description above
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[boring-cyborg]

Congratulations on your first Pull Request and welcome to the Apache Airflow community! If you have any issues or are unsure about any anything please check our Contributors' Guide (https://github.com/apache/airflow/blob/main/contributing-docs/README.rst)
Here are some useful points:

• Pay attention to the quality of your code (ruff, mypy and type annotations). Our prek-hooks will help you with that.
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[potiuk]

Can you please also add it to the CI workflows (there are two steps that need to be updated) https://github.com/apache/airflow/blob/main/.github/workflows/basic-tests.yml#L297

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.

[github-actions]

Backport failed to create: v3-1-test. View the failure log Run details

Status	Branch	Result
❌	v3-1-test

You can attempt to backport this manually by running:

cherry_picker c273d8d v3-1-test

This should apply the commit to the v3-1-test branch and leave the commit in conflict state marking
the files that need manual conflict resolution.

After you have resolved the conflicts, you can continue the backport process by running:

cherry_picker --continue

[potiuk]

Backport in #59910