fix build error for latest flutter beta (3.27.0) (#2385)

Author: martinhaintz

.github/workflows/flutter_test.yml

@@ -81,7 +81,7 @@ jobs:
 
       - name: build apk
         working-directory: ./flutter/example/android
-        run: flutter build apk --debug
+        run: flutter build apk --debug --target-platform=android-x64
 
       - name: launch android emulator & run android native test
         uses: reactivecircus/android-emulator-runner@62dbb605bba737720e10b196cb4220d374026a6d #[email protected]