Fix generic can't invoke repeatedly (#814)

diff --git a/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/service/impl/GenericServiceImpl.java b/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/service/impl/GenericServiceImpl.java
index 8fe492c..11becca 100644
--- a/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/service/impl/GenericServiceImpl.java
+++ b/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/service/impl/GenericServiceImpl.java
@@ -73,7 +73,8 @@
         reference.setInterface(intf);
         reference.setVersion(version);
         reference.setGroup(group);
-
+        //Keep it consistent with the ConfigManager cache
+        reference.setSticky(false);
         try {
             removeGenericSymbol(parameterTypes);
             GenericService genericService = reference.get();