typo fix

Examples/simple-fcm-client/app/Listeners.js

@@ -49,7 +49,7 @@ export function registerAppListener(navigation){
     console.log("Notification", notif);
 
     if(Platform.OS ==='ios' && notif._notificationType === NotificationType.WillPresent && !notif.local_notification){
-      // this notification is only to decide if you want to show the notification when user if in forground.
+      // this notification is only to decide if you want to show the notification when user if in foreground.
       // usually you can ignore it. just decide to show or not.
       notif.finish(WillPresentNotificationResult.All)
       return;