Bump katex from 0.16.19 to 0.16.22 in /docs

Bumps [katex](https://github.com/KaTeX/KaTeX) from 0.16.19 to 0.16.22.
- [Release notes](https://github.com/KaTeX/KaTeX/releases)
- [Changelog](https://github.com/KaTeX/KaTeX/blob/main/CHANGELOG.md)
- [Commits](KaTeX/KaTeX@v0.16.19...v0.16.22)

---
updated-dependencies:
- dependency-name: katex
  dependency-version: 0.16.22
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]