code: func (is *InfoSyncer) RemoveServerInfo() {
  	if is.etcdCli == nil {
  		return
  	}
  	err := ddl.DeleteKeyFromEtcd(is.serverInfoPath, is.etcdCli, keyOpDefaultRetryCnt, keyOpDefaultTimeout)
  	if err != nil {
  		logutil.Logger(context.Background()).Error("remove server info failed", zap.Error(err))
  	}
  }
docs: // RemoveServerInfo remove self server static information from etcd.