Bump zipp from 3.20.2 to 3.21.0

Bumps [zipp](https://github.com/jaraco/zipp) from 3.20.2 to 3.21.0.
- [Release notes](https://github.com/jaraco/zipp/releases)
- [Changelog](https://github.com/jaraco/zipp/blob/main/NEWS.rst)
- [Commits](jaraco/zipp@v3.20.2...v3.21.0)

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

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

docs/requirements.txt

@@ -28,4 +28,4 @@ requests==2.32.3
 six==1.16.0
 urllib3==2.2.3
 watchdog==6.0.0
-zipp==3.20.2
+zipp==3.21.0