chore: Target main branch to enable manual trigger for workflow

Author: lqiu96

.github/workflows/dependency_compatibility_test.yaml

@@ -1,6 +1,9 @@
 name: Dependency Compatibility Test
 
 on:
+  pull_request:
+    branches:
+      - 'main'
   workflow_dispatch:
   schedule:
     - cron: '0 1 * * *' # Nightly at 1am