fix in consul discovery

consul/discovery.go

@@ -102,13 +102,14 @@ func (s *Service) Register() error {
 	return nil
 }
 func (s *Service) Unregister() error {
+	s.ttlTicker.Stop()
+	s.hcTicker.Stop()
+
 	s.client.Catalog().Deregister(&consul.CatalogDeregistration{
 		Address:   s.Address,
 		ServiceID: s.GetID(),
 	}, nil)
 
-	s.ttlTicker.Stop()
-
 	return s.agent.ServiceDeregister(s.GetID())
 }