Run only when a -md file changes

.github/workflows/validate_markdown.yml

@@ -2,9 +2,13 @@ name: Validate Markdown
 
 on:
   pull_request:
+    paths:
+      - '**/*.md'
   push:
+    paths:
+      - '**/*.md'
   workflow_dispatch:
-      
+
 jobs:
   markdown-lint:
     name: Markdown Lint