Bump markdownz from 9.1.5 to 9.1.6

Bumps [markdownz](https://github.com/zooniverse/markdownz) from 9.1.5 to 9.1.6.
- [Release notes](https://github.com/zooniverse/markdownz/releases)
- [Changelog](https://github.com/zooniverse/markdownz/blob/main/CHANGELOG.md)
- [Commits](zooniverse/markdownz@v9.1.5...v9.1.6)

---
updated-dependencies:
- dependency-name: markdownz
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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