Merge with distutils@129480b

[jaraco]

• Move import of _msvccompiler into the imports section. Skip only those tests that fail based on winreg.
• Remove test suite construction in distutils.tests
• Remove unittest cruft
• Replace EnvironGuard with a pytest fixture.
• DOC: Extend Windows rpath error message with likely cause
• Implement ZLIB_SUPPORT as a pytest fixture.
• 👹 Feed the hobgoblins (delint).
• ⚫ Fade to black.
• Extract expected values into a single list.
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• 👹 Feed the hobgoblins (delint).
• Replace if/else with simple algebra.
• Consolidate 'format_command' and 'format_commands' now that order is retained in dicts.
• Consolidate messaging when runtime_library_dirs is indicated.
• Fix issue with Setuptools integration.
• Rewrite comment in imperative voice. Use bulleted list for clarity. Short circuit when functionality isn't required, rather than leaving a dangling empty branch.
• Extract _library_root to disentangle that concern from the other calculations.
• Rewrite the comment to focus on the mechanics and not the author.
• Eliminate repetition by iterating over the problem space.
• Calculate the CFLAGS match early and simply include that in the choice on whether to change the root.
• Assign result to a check and use that to consolidate return into a single expression.
• ⚫ Fade to black.

Summary of changes

Closes

Pull Request Checklist

• Changes have tests
• News fragment added in changelog.d/.
  (See documentation for details)