fix unit test failures

Author: xijunmu

ambari-metrics-timelineservice/src/test/java/org/apache/ambari/metrics/core/timeline/AbstractMiniHBaseClusterTest.java

@@ -93,7 +93,7 @@ protected static void setUpTestDriver(ReadOnlyProps serverProps, ReadOnlyProps c
     }
   }
 
-  private static String checkClusterInitialized(ReadOnlyProps serverProps) throws Exception {
+  protected static String checkClusterInitialized(ReadOnlyProps serverProps) throws Exception {
     if(!clusterInitialized) {
       url = setUpTestCluster(config, serverProps);
       clusterInitialized = true;