build(deps): bump DavidAnson/markdownlint-cli2-action from 9 to 15

Bumps [DavidAnson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action) from 9 to 15.
- [Release notes](https://github.com/davidanson/markdownlint-cli2-action/releases)
- [Commits](DavidAnson/markdownlint-cli2-action@v9...v15)

---
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/lint.yml

@@ -32,7 +32,7 @@ jobs:
     if: (github.event_name == 'pull_request' && !contains(github.event.pull_request.labels.*.name, 'skip workflows')) || github.event_name == 'push'
     steps:
       - uses: actions/checkout@v4
-      - uses: DavidAnson/markdownlint-cli2-action@v9
+      - uses: DavidAnson/markdownlint-cli2-action@v15
         with:
           globs: |
             **/*.md