Update workflow

Author: TalbotGooday

.github/workflows/main.yml

@@ -1,6 +1,8 @@
 name: Android CI
 
-on: [push]
+on:
+  push:
+    branches: [ master ]
 
 jobs:
   build:
@@ -14,4 +16,4 @@ jobs:
       with:
         java-version: 1.8
     - name: Build with Gradle
-      run: ./gradlew build
+      run: sudo ./gradlew build