Add push notification icon

app/src/google/AndroidManifest.xml

@@ -16,6 +16,10 @@
             android:name="com.google.firebase.messaging.default_notification_channel_id"
             android:value="@string/notification_channel_id" />
 
+        <meta-data
+            android:name="com.google.firebase.messaging.default_notification_icon"
+            android:resource="@drawable/ic_stat_notify" />
+
         <service android:name=".ManagerMessagingService">
             <intent-filter>
                 <action android:name="com.google.firebase.MESSAGING_EVENT" />