public async void Should_ReturnNullForSpecificShoppingList()
        {
            var options = ReturnDbContextOptions("Should_ReturnNullForSpecificShoppingList");

            // Arrange
            using (var context = new ShoppingListContext(options))
            {
                var sut = new ShoppingListController(new Repository(context));

                // Act
                var result = await sut.GetShoppingListWithRelatedItemsAsync(5);

                // Assert
                Assert.Null(result.Value);
            }
        }