Bump DavidAnson/markdownlint-cli2-action from 17 to 18

Bumps [DavidAnson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action) from 17 to 18.
- [Release notes](https://github.com/davidanson/markdownlint-cli2-action/releases)
- [Commits](DavidAnson/markdownlint-cli2-action@v17...v18)

---
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/markdown.yaml

@@ -96,7 +96,7 @@ jobs:
           dry: true
           dry_no_fail: true
     - name: Lint
-      uses: DavidAnson/markdownlint-cli2-action@v17
+      uses: DavidAnson/markdownlint-cli2-action@v18
       with:
         fix: true
         config: ${{ inputs.config-lint-path || '.github/config/.markdownlint.json' }}