build(deps): bump mdast-util-to-hast from 13.1.0 to 13.2.1 in /docs (#6012)

Bumps [mdast-util-to-hast](https://github.com/syntax-tree/mdast-util-to-hast) from 13.1.0 to 13.2.1.
- [Release notes](https://github.com/syntax-tree/mdast-util-to-hast/releases)
- [Commits](syntax-tree/mdast-util-to-hast@13.1.0...13.2.1)

---
updated-dependencies:
- dependency-name: mdast-util-to-hast
  dependency-version: 13.2.1
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]