Check the case with invalid token

src/test/dummy_tcp_sockets.rs

@@ -85,6 +85,12 @@ impl DummyTCPServer {
                 .unwrap();
         }
     }
+
+    pub async fn loop_conn_square_operations(&self) {
+        loop {
+            self.next_conn_square_operations().await
+        }
+    }
 }
 
 pub async fn dummy_tcp_client_read_conn(port: u16) -> Vec<u8> {