fix tag route display addresses bug (#785)

diff --git a/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/model/domain/Tag.java b/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/model/domain/Tag.java
index 75ea77e..fe9c3ff 100644
--- a/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/model/domain/Tag.java
+++ b/dubbo-admin-server/src/main/java/org/apache/dubbo/admin/model/domain/Tag.java
@@ -17,9 +17,11 @@
 
 package org.apache.dubbo.admin.model.domain;
 
+import java.util.List;
+
 public class Tag {
-    String name;
-    String[] addresses;
+    private String name;
+    private List<String> addresses;
 
     public String getName() {
         return name;
@@ -29,11 +31,11 @@
         this.name = name;
     }
 
-    public String[] getAddresses() {
+    public List<String> getAddresses() {
         return addresses;
     }
 
-    public void setAddresses(String[] addresses) {
+    public void setAddresses(List<String> addresses) {
         this.addresses = addresses;
     }
 }