*Fix graceful shutdown notify failure

Signed-off-by: provenceee <[email protected]>

sermant-plugins/sermant-service-registry/spring-cloud-registry-service/src/main/java/io/sermant/registry/service/cache/AddressCache.java

@@ -53,7 +53,7 @@ public void onRemoval(RemovalNotification<Object, Object> notification) {
                         System.out.println(Thread.currentThread().getName() + LocalDateTime.now() + "remove"
                                 + notification.getKey());
                         System.out.println(Thread.currentThread().getName() + LocalDateTime.now() + "remove"
-                                + notification.getValue());
+                                + notification.getCause());
                     }
                 })
                 .build();