Update DavidAnson/markdownlint-cli2-action action to v19

| datasource  | package                             | from | to  |
| ----------- | ----------------------------------- | ---- | --- |
| github-tags | DavidAnson/markdownlint-cli2-action | v18  | v19 |


Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/markdown-linting.yml

@@ -11,7 +11,7 @@ jobs:
       runs-on: ubuntu-latest
       steps:
         - uses: actions/checkout@v4
-        - uses: DavidAnson/markdownlint-cli2-action@v18
+        - uses: DavidAnson/markdownlint-cli2-action@v19
           with:
             config: '.markdownlint.json'
             globs: |