Bump DavidAnson/markdownlint-cli2-action from 18 to 19

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]>

.github/workflows/github.yml

@@ -404,7 +404,7 @@ jobs:
             python3 CI/validate_json.py
 
         - name: Validate Markdown
-          uses: DavidAnson/markdownlint-cli2-action@v18
+          uses: DavidAnson/markdownlint-cli2-action@v19
           with:
             config: 'CI/example.markdownlint-cli2.jsonc'
             globs: '**/*.md'