title: Flutter: How to enable Notification Sound
body: <p>I am developing flutter application, I want to enable notification sound. I have integrate FCM &amp; used flutterLocalNotificationsPlugin.
  <a href="https://i.stack.imgur.com/WZ0uF.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/WZ0uF.jpg" alt="This notification sound setting is disabled by default in app setting. I have to enable this setting" /></a></p>
  <pre><code>var androidPlatformChannelSpecifics = new AndroidNotificationDetails(
      'com.testApp', 'fcm', 'android',
      icon: 'notif_icon',
      color: Color(0xFFFFC33E),
      importance: Importance.max,
      priority: Priority.max,
      playSound: true,
      sound: RawResourceAndroidNotificationSound('slow_spring_board'),
      groupKey: 'com.testApp');
  var iOSPlatformChannelSpecifics =
      new IOSNotificationDetails(threadIdentifier: 'com.testApp');
  var platformChannelSpecifics = new NotificationDetails(
      android: androidPlatformChannelSpecifics,
      iOS: iOSPlatformChannelSpecifics);
  await flutterLocalNotificationsPlugin.show(
    0,
    notification.title,
    notification.body,
    platformChannelSpecifics,
    payload: json.encode(message.data),
  );
  </code></pre>