Remove class references in changelogs

[potiuk]

PyPI does not handle class references in changelogs.
Since we want changelogs to be part of PyPI readmes,
we need to remove those.

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^ Add meaningful description above

Read the Pull Request Guidelines for more information.
In case of fundamental code change, Airflow Improvement Proposal (AIP) is needed.
In case of a new dependency, check compliance with the ASF 3rd Party License Policy.
In case of backwards incompatible changes please leave a note in UPDATING.md.

[potiuk]

BTW. Need to add python -m readme_renderer README.rst as part of the preparation step :)

[uranusjr]

Does twine check not already do that? https://twine.readthedocs.io/en/latest/#twine-check

[potiuk]

Does twine check not already do that? https://twine.readthedocs.io/en/latest/#twine-check

It does. but so far we run it as 'last' step already after the doc-change was merged and packages were prepared. But yeah, it could be running twine check as the step in CI/preparation process rather than readme_renderer, to be more complete.

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.