Bump pygments from 2.19.2 to 2.20.0 in /requirements/docs

Bumps [pygments](https://github.com/pygments/pygments) from 2.19.2 to 2.20.0.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](pygments/pygments@2.19.2...2.20.0)

---
updated-dependencies:
- dependency-name: pygments
  dependency-version: 2.20.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements/docs/requirements.txt

@@ -10,7 +10,7 @@ importlib-metadata==8.7.0 ; python_version == "3.9"
 jinja2==3.1.6 ; python_version >= "3.9"
 markupsafe==3.0.2 ; python_version >= "3.9"
 packaging==25.0 ; python_version >= "3.9"
-pygments==2.19.2 ; python_version >= "3.9"
+pygments==2.20.0 ; python_version >= "3.9"
 requests==2.32.4 ; python_version >= "3.9"
 snowballstemmer==3.0.1 ; python_version >= "3.9"
 sphinx-rtd-theme==3.0.2 ; python_version >= "3.9"