Add GitHub Actions workflow to run validate_plugins.py

Author: ckdash-git

.github/workflows/validate.yml

@@ -0,0 +1,21 @@
+name: Validate Plugins
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  validate:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version: '3.12'
+        
+    - name: Run Plugin Validator
+      run: python3 validate_plugins.py