Bump sphinx-click from 5.1.0 to 6.0.0 in /docs

Bumps [sphinx-click](https://github.com/click-contrib/sphinx-click) from 5.1.0 to 6.0.0.
- [Release notes](https://github.com/click-contrib/sphinx-click/releases)
- [Commits](click-contrib/sphinx-click@5.1.0...6.0.0)

---
updated-dependencies:
- dependency-name: sphinx-click
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

docs/requirements.txt

@@ -1,4 +1,4 @@
 furo==2024.1.29
 myst_parser==2.0.0
 sphinx==7.2.6
-sphinx-click==5.1.0
+sphinx-click==6.0.0