public void VendingMachineItem_should_decrement_the_Quantity()
{
var testOrderNumber = _fixture.Create <int>();
var testProductName = _fixture.Create <string>();
var testPrice = _fixture.Create <decimal>();
var testTotalItem = _fixture.Create <int>();
var testPurchaseQuantity = 1;
var cut = new MM(testOrderNumber, testProductName, testPrice, testTotalItem);
cut.DecrementItem(testPurchaseQuantity);
cut.TotalItem.Should().Be(testTotalItem - testPurchaseQuantity);
}