Bump pygments from 2.15.1 to 2.16.1

Bumps [pygments](https://github.com/pygments/pygments) from 2.15.1 to 2.16.1.
- [Release notes](https://github.com/pygments/pygments/releases)
- [Changelog](https://github.com/pygments/pygments/blob/master/CHANGES)
- [Commits](pygments/pygments@2.15.1...2.16.1)

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

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

requirements.txt

@@ -1,4 +1,4 @@
 mkdocs==1.5.1
 mkdocs-material==9.1.21
-pygments==2.15.1
+pygments==2.16.1
 pymdown-extensions==10.1