public void EnqueueRollbackTest()
        {
            Parallel.For(0, 3, _ =>
            {
                _queue.Enqueue(_sampleOutboundMessage);
            });

            _queue.Rollback();

            _queue.Length.Should().Be(0);
        }
        public async Task EnqueueRollbackTest()
        {
            Parallel.For(0, 3, _ =>
            {
                _queue.Enqueue(_sampleOutboundMessage);
            });

            await _queue.Rollback();

            (await _queue.GetLength()).Should().Be(0);
        }