build(deps): bump urllib3 from 2.6.0 to 2.6.3 in /docs

Bumps [urllib3](https://github.com/urllib3/urllib3) from 2.6.0 to 2.6.3.
- [Release notes](https://github.com/urllib3/urllib3/releases)
- [Changelog](https://github.com/urllib3/urllib3/blob/main/CHANGES.rst)
- [Commits](https://github.com/urllib3/urllib3/compare/2.6.0...2.6.3)

---
updated-dependencies:
- dependency-name: urllib3
  dependency-version: 2.6.3
  dependency-type: direct:production
...

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

docs/requirements.txt

@@ -73,5 +73,5 @@ text-unidecode==1.3
 twine==6.1.0
 typing_extensions==4.13.2
 Unidecode==1.4.0
-urllib3==2.6.0
+urllib3==2.6.3
 zipp==3.22.0