Update validate_yamllint.yml

.github/workflows/validate_yamllint.yml

@@ -9,9 +9,19 @@ on:
 
 jobs:
   code_scan:
-    name: Validate Blueprint YAML
+    name: Validate YAML
     runs-on: "ubuntu-latest"
     steps:
-      - uses: actions/checkout@v4.1.0
+      - name: Check out code
+        uses: actions/checkout@v4.1.0
+
+      - name: Identify changed files
+        uses: tj-actions/changed-files@v41
+        id: changed-files
+        with:
+          files: '**/*.y*ml'
+          separator: ","
+
       - name: Validate YAML
-        run: yamllint -c "./.rules/yamllint.yml"
+        if: steps.changed-files.outputs.any_changed == 'true'
+        run: yamllint -c "./.rules/yamllint.yml" --list-files -f github -s "${{ steps.changed-files.outputs.all_changed_files }}"