int getOutOfQuotaResourcesInQueue() {
    return outOfQuotaResourcesInQueue;
  }
@return the value of {@code outOfQuotaResourcesInQueue} representing the count of out of {@link QuotaResource}s with
requests in the queue.
ambry-router/src/main/java/com/github/ambry/router/QuotaAwareOperationController.java