Bump pypa/cibuildwheel from 2.20.0 to 2.21.1

Bumps [pypa/cibuildwheel](https://github.com/pypa/cibuildwheel) from 2.20.0 to 2.21.1.
- [Release notes](https://github.com/pypa/cibuildwheel/releases)
- [Changelog](https://github.com/pypa/cibuildwheel/blob/main/docs/changelog.md)
- [Commits](pypa/cibuildwheel@v2.20.0...v2.21.1)

---
updated-dependencies:
- dependency-name: pypa/cibuildwheel
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/build-wheels.yml

@@ -25,7 +25,7 @@ jobs:
           platforms: all
 
       - name: Build ${{ matrix.os }} wheels
-        uses: pypa/cibuildwheel@v2.20.0
+        uses: pypa/cibuildwheel@v2.21.1
         env:
           # we only support what's supported by wxPython, therefore we skip:
           #  * PyPy Python implementation