[3.8] bpo-44828: Avoid tkinter file dialog failure on macOS 12 Monterey (GH-29276)

[miss-islington]

when using the Tk 8.6.11 provided by python.org macOS installers.
Patch by Marc Culler of the Tk project.
(cherry picked from commit be8318b)

Co-authored-by: Ned Deily [email protected]

https://bugs.python.org/issue44828

[ned-deily]

@ambv, As we discussed, here is a courtesy backport of the Monterey Tk fix to the 3.8 branch. We don't expect to ever use it since 3.8 is the security-fix-only phase of its life cycle and thus we no longer provide binary installers for it. BTW, the Docs build failure is addressed in open PR #29245.

[miss-islington]

@ned-deily: Status check is done, and it's a failure ❌ .

[ambv]

The failure is due to a recent release of docutils 0.18, so far incompatible with Sphinx (sphinx-doc/sphinx#9777). This was already fixed in 3.8 by #29245 (thanks, Ned!). So I'll be landing this.