public async Task GetCatById_ForId_Successful()
        {
            var lastCat = Cats.LastOrDefault();
            var cat     = await CatController.GetById(lastCat.Id);

            cat.Id.Should().Be(lastCat.Id);
        }
        public async Task GetCatById_ForId_Successful()
        {
            var lastCat = TestData.Cats.LastOrDefault();
            var result  = await CatController.GetById(lastCat.Id) as OkObjectResult;

            var cat = result.Value as Cat;

            cat.Id.Should().Be(lastCat.Id);
        }