github: [skip ci]: bump DavidAnson/markdownlint-cli2-action
Bumps [DavidAnson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action) from 18 to 19.
- [Release notes](https://github.com/davidanson/markdownlint-cli2-action/releases)
- [Commits](https://github.com/davidanson/markdownlint-cli2-action/compare/v18...v19)
---
updated-dependencies:
- dependency-name: DavidAnson/markdownlint-cli2-action
dependency-type: direct:production
update-type: version-update:semver-major
...
Signed-off-by: dependabot[bot] <[email protected]>