This fixes #76 where you a TooManyProviderTokenUpdates if you send notifications to multiple topics over one connection. As Apple states here https://developer.apple.com/documentation/usernotifications/setting_up_a_remote_notification_server/establishing_a_token-based_connection_to_apns#2943374 one connection shall use only one single JWT token which should be refreshed no more than once every 20 minutes and no less than once every 60 minutes.