default CompletableFuture<Boolean> balance() {
    return balance(BalanceRequest.defaultInstance()).thenApply(BalanceResponse::isBalancerRan);
  }
Invoke the balancer. Will run the balancer and if regions to move, it will go ahead and do the
reassignments. Can NOT run for various reasons. Check logs.
@return True if balancer ran, false otherwise. The return value will be wrapped by a
        {@link CompletableFuture}.
hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncAdmin.java