Update test_builddocsite.yml

trigger w/f on push to main only

Author: briantoby

.github/workflows/test_builddocsite.yml

@@ -15,7 +15,11 @@
 name: build GSAS-II web site w/test MD Help
 
 #on: [workflow_dispatch] 
-on: [push, workflow_dispatch]
+on: 
+  push:
+    branches:  
+      - "main"  
+  workflow_dispatch:
 
 permissions:
   contents: write