Bump pymdown-extensions from 9.8 to 10.0

Bumps [pymdown-extensions](https://github.com/facelessuser/pymdown-extensions) from 9.8 to 10.0.
- [Release notes](https://github.com/facelessuser/pymdown-extensions/releases)
- [Commits](facelessuser/pymdown-extensions@9.8...10.0)

---
updated-dependencies:
- dependency-name: pymdown-extensions
  dependency-type: direct:production
...

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

requirements.docs.txt

@@ -2,4 +2,4 @@ markdown-include==0.7.0
 mkdocs-material-extensions==1.1
 mkdocs-material==8.5.10
 mkdocs==1.4.2
-pymdown-extensions==9.8
+pymdown-extensions==10.0