bump markdownlint-cli2-action@v16

Author: dklimpel

.github/workflows/docs.yaml

@@ -20,7 +20,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: DavidAnson/markdownlint-cli2-action@v13
+      - uses: DavidAnson/markdownlint-cli2-action@v16
         with:
           globs: |
             docs/**/*.md