Tweak GHA trigger events

JohnTitor · JohnTitor · commit 9f9da4bd7237 · 2020-10-18T01:12:00.000+09:00
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
@@ -1,5 +1,10 @@
 name: CI
-on: [push, pull_request]
+on:
+  pull_request:
+    types: [opened, synchronize, reopened]
+  push:
+    branches:
+      - master
 
 jobs:
   test:
