@Override
  public void cancel() {

  }
Instantiates {@link MySqlReportAggregatorTask}.
@param manager The {@link HelixManager} to retrieve all storage nodes.
@param relevantTimePeriodInMs relevant time period in ms within which values are considered to be valid. Values
                              outside of this period will be ignored.
@param statsReportType the type of stats report
@param accountStatsStore The {@link AccountStatsStore} to retrieve stats and store aggregated stats.
@param callback a callback which will be invoked when the aggregation report has been generated successfully.
@param clusterMapConfig the {@link ClusterMapConfig} associated with helix participant.
@param registry the {@link MetricRegistry}.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/MySqlReportAggregatorTask.java