fix: exit when receiving STOP signal (worker)

src/communication.py

@@ -89,10 +89,13 @@ class ClusterCommunicationModule():
             data = {'host': self.host, 'GPU': self.node_manager.GPU, 'GPU_num': self.node_manager.GPU_num}
             self.client_sock.send(json.dumps(data).encode())
         elif command == '[STOP]':
+            print("Receive STOP signal")
             self.node_manager.docker_client.swarm.leave()
             data = {'host': self.host}
             self.client_sock.send(f'[STOP_CHECK]  {json.dumps(data)}'.encode())
 
+            self.node_manager.exit()
+
         return True
 
     def request(self, host):                    # master side