add buildFeatures

Author: SelaseKay

packages/firebase_snippets_app/android/app/build.gradle

@@ -52,6 +52,10 @@ android {
         versionName flutterVersionName
     }
 
+    buildFeatures {
+        buildConfig true
+    }
+
     buildTypes {
         release {
             // TODO: Add your own signing config for the release build.