Remove the packet variable from cancel_notify function

[EnotYoyo]

    def stop_notify(self, packet: Packet):
        if self._notify_future is None:
            raise PySpheroRuntimeError("Future not found")

        logger.debug(f"[NOTIFY_WORKER {packet}] Cancel")
        self._notify_future.cancel()
        self._notify_future = None

[EnotYoyo]

Done