run builds on PRs also

Author: bradmartin

.github/workflows/build.yml

@@ -1,7 +1,7 @@
 name: Build CI
 
 # Trigger the workflow on push or pull request
-on: [push]
+on: [push, pull_request]
 
 jobs:
   build:
@@ -45,4 +45,4 @@ jobs:
       - name: Build iOS Demo App
         run: |
           cd demo
-          tns build ios --env.uglify
+          tns build ios --env.uglify