fix: ensure clusters order in envclusters openapi

Author: uucloud

CHANGES.md

@@ -19,6 +19,7 @@ Apollo 2.4.0
 * [Feature: openapi query namespace support not fill item](https://github.com/apolloconfig/apollo/pull/5249)
 * [Refactor: align database ClusterName and NamespaceName fields lengths](https://github.com/apolloconfig/apollo/pull/5263)
 * [Feature: Added the value length limit function for AppId-level configuration items](https://github.com/apolloconfig/apollo/pull/5264)
+* [Fix: ensure clusters order in envClusters open api](https://github.com/apolloconfig/apollo/pull/5277)
 
 ------------------
 All issues and pull requests are [here](https://github.com/apolloconfig/apollo/milestone/15?closed=1)

apollo-common/src/main/java/com/ctrip/framework/apollo/common/utils/BeanUtils.java

@@ -28,6 +28,7 @@
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -164,7 +165,7 @@ public static <K, V> Map<K, List<V>> aggByKeyToList(String key, List<?> list) {
    */
   @SuppressWarnings("unchecked")
   public static <K> Set<K> toPropertySet(String key, List<?> list) {
-    Set<K> set = new HashSet<>();
+    Set<K> set = new LinkedHashSet<>();
     if (CollectionUtils.isEmpty(list)) {// 防止外面传入空list
       return set;
     }