@VisibleForTesting
  public static Predicate<GatewaySenderEventImpl> getIsLastEventInTransactionPredicate() {
    return GatewaySenderEventImpl::isLastEventInTransaction;
  }
Take will choose a random BucketRegionQueue which is primary and will take the head element
from it.
geode-core/src/main/java/org/apache/geode/internal/cache/wan/parallel/ParallelGatewaySenderQueue.java