Bump DavidAnson/markdownlint-cli2-action from 14 to 15

Bumps [DavidAnson/markdownlint-cli2-action](https://github.com/davidanson/markdownlint-cli2-action) from 14 to 15.
- [Release notes](https://github.com/davidanson/markdownlint-cli2-action/releases)
- [Commits](DavidAnson/markdownlint-cli2-action@v14...v15)

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

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/lint.yml

@@ -19,4 +19,4 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - name: Run markdownlint
-      uses: DavidAnson/markdownlint-cli2-action@v14
+      uses: DavidAnson/markdownlint-cli2-action@v15