Bump markdownlint-rule-helpers from 0.17.2 to 0.28.0

Bumps [markdownlint-rule-helpers](https://github.com/DavidAnson/markdownlint) from 0.17.2 to 0.28.0.
- [Changelog](https://github.com/DavidAnson/markdownlint/blob/main/CHANGELOG.md)
- [Commits](DavidAnson/markdownlint@v0.17.2...v0.28.0)

---
updated-dependencies:
- dependency-name: markdownlint-rule-helpers
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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