apollo-portal/src/main/java/com/ctrip/framework/apollo/portal/api/AdminServiceAPI.java/AdminServiceAPI/updateItemsByChangeSet
class AdminServiceAPI:    public void updateItemsByChangeSet(String appId, Env env, String clusterName, String namespace,
        ItemChangeSets changeSets) {
      restTemplate.post(env, "apps/{appId}/clusters/{clusterName}/namespaces/{namespaceName}/itemset",
          changeSets, Void.class, appId, clusterName, namespace);
    }