private static POSContext GenerateMockContextData()
        {
            var options = new DbContextOptionsBuilder <POSContext>()
                          .UseInMemoryDatabase("TodoList").Options;
            POSContext context = new POSContext(options);

            context = AddingToCartTest.AddItem(context, MockItem.GenerateMockItem1());
            context = AddingToCartTest.AddItem(context, MockItem.GenerateMockItem2());
            context = AddingToCartTest.AddItem(context, MockItem.GenerateMockItem3());
            return(context);
        }