`ws` `singleMode:true` 连接上5秒钟会断开, `singleMode: false`则不会

[sxd1140]

2.9.1

adapters:
  - http
  - ws
debug: true
enableVerify: false
singleMode: true
cacheSize: 4096
adapterSettings:
  http:
    host: 0.0.0.0
    port: 8888
    cors: ["*"]
  ws:
    host: 0.0.0.0
    port: 9999

在断开之前发送消息也正常. 收到

{"syncId": "", "data": {"code": 0, "session": "SINGLE_SESSION"}}

后5秒钟断开连接.