Validate markdown

.github/workflows/validate_markdown.yml

@@ -0,0 +1,23 @@
+name: Validate Markdown
+
+on:
+  pull_request:
+  push:
+  workflow_dispatch:
+      
+jobs:
+  markdown-check:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Check out code
+      uses: actions/checkout@v4.1.0
+
+    # https://github.com/actionshub/markdownlint
+    - name: Markdown Lint
+      uses: actionshub/markdownlint@main
+
+    # https://github.com/gaurav-nelson/github-action-markdown-link-check  
+    - name: Markdown links
+      uses: gaurav-nelson/github-action-markdown-link-check@v1
+      with:
+        check-modified-files-only: 'yes'