chore: socket.io的transports默认只使用websocket

src/index.js

@@ -47,7 +47,7 @@ if (SERVER_MODE !== 'static') {
         cors: {
             origin: '*',
             methods: ['GET', 'POST'],
-            transports: ['websocket', 'polling', 'flashsocket'],
+            transports: ['websocket'],
             credentials: false
         }
     });