Bump mistune from 2.0.4 to 3.2.1

Bumps [mistune](https://github.com/lepture/mistune) from 2.0.4 to 3.2.1.
- [Release notes](https://github.com/lepture/mistune/releases)
- [Changelog](https://github.com/lepture/mistune/blob/main/docs/changes.rst)
- [Commits](lepture/mistune@v2.0.4...v3.2.1)

---
updated-dependencies:
- dependency-name: mistune
  dependency-version: 3.2.1
  dependency-type: direct:production
...

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

Author: dependabot[bot]

requirements.txt

@@ -1 +1 @@
-mistune==2.0.4
+mistune==3.2.1