修复获取TopN的Broker指标时，会出现部分指标缺失的问题(#657)

修复获取TopN的Broker指标时，会出现部分指标缺失的问题

km-persistence/src/main/java/com/xiaojukeji/know/streaming/km/persistence/es/dao/BrokerMetricESDAO.java

@@ -92,7 +92,7 @@ public class BrokerMetricESDAO extends BaseMetricESDAO {
         Table<String, Long, List<MetricPointVO>> table = HashBasedTable.create();
 
         //2、查询指标
-        for(String metric : metricBrokerIds.keySet()){
+        for(String metric : metrics) {
             table.putAll(
                     this.listBrokerMetricsByBrokerIds(
                             clusterPhyId,