code: def stop(self):
          
          LOGGER.debug("InjectorService.stop")
          self.driver.stop()
          InjectorUITreeService.requester = None
          InjectorCachedRegistryFactoryService.requester = None
          InjectorCachedComponentService.requester = None
          InjectorCachedGearService.requester = None
docs: stop the injector service. By the way stoping all Pykka actors if not cleanly closed.
          :return: