Python 3.11 upgrade cleanup

[seanbudd]

Link to issue number:

Clean up of #15544

Summary of the issue:

• from __future__ import annotations can be removed
• gettext now supports pgettext and npgettext, NVDA's implementations can be abandoned
• enum patches can be removed Remove enum patches on Python 3.11 #15531

Description of user facing changes

Should be none

Description of development approach

Straight forward code deprecation or implementation of noted comments

Testing strategy:

Alpha testing needed.
Basic manual smoke test performed

Known issues with pull request:

None

Code Review Checklist:

• Documentation:
  • Change log entry
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• API is compatible with existing add-ons.
• Security precautions taken.

[AppVeyorBot]

• PASS: Translation comments check.
• PASS: Unit tests.
• FAIL: Lint check. See test results for more information.
• PASS: System tests (tags: installer NVDA).
• Build (for testing PR): https://ci.appveyor.com/api/buildjobs/4sdil2ex343nl788/artifacts/output/nvda_snapshot_pr15546-29636,9230fb0c.exe
• CI timing (mins):
  INIT 0.0,
  INSTALL_START 0.8,
  INSTALL_END 0.9,
  BUILD_START 0.0,
  BUILD_END 22.6,
  TESTSETUP_START 0.0,
  TESTSETUP_END 0.3,
  TEST_START 0.0,
  TEST_END 7.8,
  FINISH_END 0.2

See test results for failed build of commit 9230fb0c5f

[codeofdusk]

This PR resolves a number of "found unreachable objects" errors in Chrome and should be merged as soon as practical.