Thanks Tim Graham for spotting the error.

DatabaseWrapper.prepare_database has been introduced in 307de67073.

Thanks Kenial S. Lee for the initial patch and Tim Graham for
the review.

Thanks GreenAsJade.

This is helpful if you build and test documentation updates in
your development env.

Copied from CPython's Doc/Makefile.

Add missing dot

Refs #23947 -- Worked around a bug in Python that prevents deprecation warnings from appearing in tests.

Thanks Diego Guimarãesi and Florian Apolloner.

Thanks Carl Meyer for review.