Build: Run CI on both pull requests and pushes, and run buildDebug instead of assembleDebug

Author: zhanghai

.github/workflows/android.yml

@@ -1,6 +1,6 @@
 name: Android CI
 
-on: [push]
+on: [pull_request, push]
 
 jobs:
   build:
@@ -12,10 +12,10 @@ jobs:
       uses: actions/checkout@v3
       with:
         submodules: true
-    - name: Set up JDK 17
-      uses: actions/setup-java@v3
+    - name: Set up JDK 21
+      uses: actions/setup-java@v4
       with:
         distribution: 'temurin'
-        java-version: '17'
+        java-version: '21'
     - name: Build with Gradle
-      run: ./gradlew assembleDebug lintVitalRelease
+      run: ./gradlew buildDebug lintVitalRelease