Bump importlib-metadata from 6.7.0 to 6.8.0

Bumps [importlib-metadata](https://github.com/python/importlib_metadata) from 6.7.0 to 6.8.0.
- [Release notes](https://github.com/python/importlib_metadata/releases)
- [Changelog](https://github.com/python/importlib_metadata/blob/main/NEWS.rst)
- [Commits](python/importlib_metadata@v6.7.0...v6.8.0)

---
updated-dependencies:
- dependency-name: importlib-metadata
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

ci-constraints-requirements.txt

@@ -48,7 +48,7 @@ idna==3.4
     # via requests
 imagesize==1.4.1
     # via sphinx
-importlib-metadata==6.7.0; python_version >= "3.8"
+importlib-metadata==6.8.0; python_version >= "3.8"
     # via
     #   keyring
     #   twine