Bump davidanson/markdownlint-cli2-action from 17.0.0 to 18.0.0 (#540)

Bumps [davidanson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action) from 17.0.0 to 18.0.0.
- [Release notes](https://github.com/davidanson/markdownlint-cli2-action/releases)
- [Commits](DavidAnson/markdownlint-cli2-action@v17.0.0...v18.0.0)

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

.github/workflows/ci.yml

@@ -23,7 +23,7 @@ jobs:
       - name: Checkout
         uses: actions/[email protected]
       - name: Check formatting
-        uses: davidanson/markdownlint-cli2-action@v17.0.0
+        uses: davidanson/markdownlint-cli2-action@v18.0.0
         with:
           globs: '**/*.md'
   build: