Revert "Fix ci: remove pkg_resource import, bump pre-commit dependencies"

[zagy]

Reverts flyingcircusio/appenv#46

With #46 appenv update-lockfile fails, so I propose to revert it.

Update lockfile with with /opt/homebrew/Cellar/python@3.12/3.12.2_1/Frameworks/Python.framework/Versions/3.12/bin/python3.12.
If you want to use a different version, set it via
 `# appenv-python-preference:` in requirements.txt.
Updating lockfile
Creating venv ...
Ensuring pip ...
Installing packages ...
Traceback (most recent call last):
  File "/….batou/./appenv", line 533, in <module>
    main()
  File "/….batou/./appenv", line 525, in main
    appenv.meta()
  File "/….batou/./appenv", line 283, in meta
    args.func(args, remaining)
  File "/….batou/./appenv", line 458, in update_lockfile
    from packaging.requirements import Requirement
ModuleNotFoundError: No module named 'packaging'

[zagy]

Superseded by #50