title: Duplicate resources on “ionic cordova build android” command. Firebase plugin
body: <p>I'm building a fresh new application for android with the following plugins and commands. Cordova plugin add cordova-plugin-fcm, ionic cordova build android.
  This is the error displayed:</p>
  
  <pre><code>Parsing json file: /home/faichi/palav-ui/platforms/android/google-services.json
          :generateDebugResources
          :mergeDebugResources
          [string/google_app_id] /home/faichi/palav-ui/platforms/android/res/values/strings.xml   [string/google_app_id]
          /home/faichi/palav-ui/platforms/android/build/generated/res/google-services/debug/values/values.xml: Error:
      Duplicate resources
      :mergeDebugResources FAILED
  
      BUILD FAILED
  
      Total time: 1.683 secs
  
      FAILURE: Build failed with an exception.
  
      * What went wrong:
      Execution failed for task ':mergeDebugResources'.
      &gt; [string/google_app_id] /home/faichi/palav-ui/platforms/android/res/values/strings.xml [string/google_app_id]
      /home/faichi/palav-ui/platforms/android/build/generated/res/google-services/debug/values/values.xml: Error:
      Duplicate resources
  
      * Try:
      Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.
      Error: /home/faichi/palav-ui/platforms/android/gradlew: Command failed with exit code 1 Error output:
      FAILURE: Build failed with an exception.
  
      * What went wrong:
      Execution failed for task ':mergeDebugResources'.
      &gt; [string/google_app_id] /home/faichi/palav-ui/platforms/android/res/values/strings.xml [string/google_app_id]
      /home/faichi/palav-ui/platforms/android/build/generated/res/google-services/debug/values/values.xml: Error:
      Duplicate resources
  </code></pre>
  
  <p>I've tried to delete the duplicate values on android\res\values\strings.xml but on each build its coming back and display the same error.</p>
  
  <p>Is this is currect way to build a cordova based application with fire bash push notification service ?</p>