public IActionResult UpdateProductOrder(int id, ProductOrder lineItem)
        {
            var updatedLineItem = _productOrderRepo.Update(id, lineItem);

            if (_productOrderRepo.GetSingleItemInOrderById(id) == null)
            {
                return(NotFound("We could not find a line item with this ID. Please try again."));
            }

            return(Ok(updatedLineItem));
        }