build(deps): bump DavidAnson/markdownlint-cli2-action

Bumps the github-actions group with 1 update: [DavidAnson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action).


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

---
updated-dependencies:
- dependency-name: DavidAnson/markdownlint-cli2-action
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: github-actions
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
         run: git ls-files -- '*.c' '*.h' | xargs clang-format --dry-run --Werror
 
       - name: Check Markdown
-        uses: DavidAnson/markdownlint-cli2-action@v17
+        uses: DavidAnson/markdownlint-cli2-action@v18
 
       - name: Check TOML formatting
         run: taplo fmt --check