Bump pymdown-extensions from 10.0 to 10.16.1 in /docs

Bumps [pymdown-extensions](https://github.com/facelessuser/pymdown-extensions) from 10.0 to 10.16.1.
- [Release notes](https://github.com/facelessuser/pymdown-extensions/releases)
- [Commits](facelessuser/pymdown-extensions@10.0...10.16.1)

---
updated-dependencies:
- dependency-name: pymdown-extensions
  dependency-version: 10.16.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

docs/requirements.txt

@@ -52,7 +52,7 @@ pygments==2.19.2 ; python_version >= "3.9" and python_version < "3.15"
 pyinstaller-hooks-contrib==2025.10 ; python_version >= "3.9" and python_version < "3.15"
 pyinstaller==6.17.0 ; python_version >= "3.9" and python_version < "3.15"
 pylint==3.3.9 ; python_version >= "3.9" and python_version < "3.15"
-pymdown-extensions==10.0 ; python_version >= "3.9" and python_version < "3.15"
+pymdown-extensions==10.16.1 ; python_version >= "3.9" and python_version < "3.15"
 pync==2.0.3 ; python_version >= "3.9" and python_version < "3.15" and sys_platform == "darwin"
 pytest-cov==7.0.0 ; python_version >= "3.9" and python_version < "3.15"
 pytest-describe==3.1.0 ; python_version >= "3.9" and python_version < "3.15"