gem related automation must run only on master

.github/workflows/bundled_gems.yml

@@ -2,14 +2,17 @@ name: bundled_gems
 
 on:
   push:
+    branches: [ "master" ]
     paths:
       - '.github/workflows/bundled_gems.yml'
       - 'gems/bundled_gems'
   pull_request:
+    branches: [ "master" ]
     paths:
       - '.github/workflows/bundled_gems.yml'
       - 'gems/bundled_gems'
   merge_group:
+    branches: [ "master" ]
     paths:
       - '.github/workflows/bundled_gems.yml'
       - 'gems/bundled_gems'