public MiniHBaseCluster startMiniCluster(int numSlaves) throws Exception {
    StartMiniClusterOption option =
      StartMiniClusterOption.builder().numRegionServers(numSlaves).numDataNodes(numSlaves).build();
    return startMiniCluster(option);
  }
Start up a minicluster of hbase, dfs and zookeeper clusters with given slave node number. All
other options will use default values, defined in {@link StartMiniClusterOption.Builder}.
@param numSlaves slave node number, for both HBase region server and HDFS data node.
@see #startMiniCluster(StartMiniClusterOption option)
@see #shutdownMiniDFSCluster()
hbase-testing-util/src/main/java/org/apache/hadoop/hbase/HBaseTestingUtility.java