How to make a release

Following https://github.com/codespell-project/codespell/pull/2523:

1. Before creating a release, ensure all supported Python versions are listed in the following places:

   1. .github/workflows/codespell-private.yml
   2. pyproject.toml
      1. The minimum version under requires-python
      2. All supported versions are listed under classifiers
   3. Ensure one version (the minimum?) is listed under appveyor.yml

2. Ensure the CI still passes after the above changes.

3. Create a published release on GitHub:

   1. Use the form v2.2.1 for the tag and the title
   2. Use autogenerated GitHub release notes

This should trigger .github/workflows/release.yml to push to PyPI, and then later conda-forge tickbot should automatically update as well.