build(deps): bump requests from 2.25.1 to 2.31.0 in /docs (#2283)

Bumps [requests](https://github.com/psf/requests) from 2.25.1 to 2.31.0.
- [Release notes](https://github.com/psf/requests/releases)
- [Changelog](https://github.com/psf/requests/blob/main/HISTORY.md)
- [Commits](psf/requests@v2.25.1...v2.31.0)

---
updated-dependencies:
- dependency-name: requests
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

docs/requirements.txt

@@ -13,7 +13,7 @@ Pygments==2.7.4
 pyparsing==2.4.7
 pytz==2021.1
 recommonmark==0.7.1
-requests==2.25.1
+requests==2.31.0
 snowballstemmer==2.1.0
 Sphinx==4.4.0
 sphinx-rtd-theme==1.0.0