public void PromotionWithCartsTests()
        {
            IPromotionServices _promotionServices = new NoPromotionServices();

            _promotionServices.SetCart(_cartService);
            Assert.Equal(245, _promotionServices.Price());
        }
        public void PromotionWithNoCartsTests()
        {
            IPromotionServices _promotionServices = new NoPromotionServices();

            Assert.Equal(0, _promotionServices.Price());
        }