Bump @github/markdownlint-github from 0.6.0 to 0.6.3 (#171)

Bumps [@github/markdownlint-github](https://github.com/github/markdownlint-github) from 0.6.0 to 0.6.3.
- [Release notes](https://github.com/github/markdownlint-github/releases)
- [Commits](github/markdownlint-github@0.6.0...v0.6.3)

---
updated-dependencies:
- dependency-name: "@github/markdownlint-github"
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>