Bump markdownlint-cli from 0.39.0 to 0.40.0

Bumps [markdownlint-cli](https://github.com/igorshubovych/markdownlint-cli) from 0.39.0 to 0.40.0.
- [Release notes](https://github.com/igorshubovych/markdownlint-cli/releases)
- [Commits](igorshubovych/markdownlint-cli@v0.39.0...v0.40.0)

---
updated-dependencies:
- dependency-name: markdownlint-cli
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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