Bump pygments from 2.18.0 to 2.20.0 in /docs

Bumps [pygments](https://github.com/pygments/pygments) from 2.18.0 to 2.20.0.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](pygments/pygments@2.18.0...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]

docs/notebook_requirements.txt

@@ -39,7 +39,7 @@ prometheus-client==0.20.0
 prompt-toolkit==3.0.47
 ptyprocess==0.7.0
 pycparser==2.22
-Pygments==2.18.0
+Pygments==2.20.0
 pyzmq==26.1.1
 qtconsole==5.5.2
 Send2Trash==1.8.3