GH-121970: Extract pydoc_topics into a new extension

[AA-Turner]

It seems the error was in #130492, the attempted fix. That PR stripped all trailing whitespace, which inadvertantley also removed the final newline, leading to syntax errors, as there were four consecutive quotation marks.

This PR reapplies the reverted commit (#131245), adds a trailing newline, and finally regenerates pydoc_data/topics.py.

A

• Issue: Improve and reorganise pyspecific #121970

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📚 Documentation preview 📚: https://cpython-previews--131256.org.readthedocs.build/

[hugovk]

Thanks! Do you have a good way to reproduce the original failure in a minimal way?

[AA-Turner]

Thanks! Do you have a good way to reproduce the original failure in a minimal way?

$ git switch -C investigate db62557e3d1b0de4ca17786bd53f9c825ad88721
$ make -CDoc pydoc-topics
$ cp Doc/build/pydoc-topics/topics.py Lib/pydoc_data/topics.py
$ git commit -am "regenerate pydoc-topics"
$ make ci