Bump md-editor-v3 from 4.21.3 to 5.8.2

Bumps [md-editor-v3](https://github.com/imzbf/md-editor-v3) from 4.21.3 to 5.8.2.
- [Release notes](https://github.com/imzbf/md-editor-v3/releases)
- [Commits](imzbf/md-editor-v3@v4.21.3...v5.8.2)

---
updated-dependencies:
- dependency-name: md-editor-v3
  dependency-version: 5.8.2
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]