default void postGetRSGroupInfo(final ObserverContext<MasterCoprocessorEnvironment> ctx,
    final String groupName) throws IOException {
  }
Called after getting region server group info of the passed groupName.
@param ctx       the environment to interact with the framework and master
@param groupName name of the group to get RSGroupInfo for
hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/MasterObserver.java