build(deps): bump babel from 2.9.1 to 2.12.1 in /docs (#2527)

Bumps [babel](https://github.com/python-babel/babel) from 2.9.1 to 2.12.1.
- [Release notes](https://github.com/python-babel/babel/releases)
- [Changelog](https://github.com/python-babel/babel/blob/master/CHANGES.rst)
- [Commits](python-babel/babel@v2.9.1...v2.12.1)

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

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

docs/requirements.txt

@@ -1,5 +1,5 @@
 alabaster==0.7.13
-Babel==2.9.1
+Babel==2.12.1
 certifi==2023.7.22
 chardet==5.1.0
 commonmark==0.9.1