public async Task GetByIdAsync_ShouldReturnNotFoundResponseGivenTheIdDoesNotMatchAnAdvertisement()
{
var nonExistentId = new Fixture().Create <int>();
_advertisementService.Setup(x => x.GetByIdAsync(nonExistentId)).ReturnsAsync((Advertisement)null);
var result = await _controller.GetByIdAsync(nonExistentId);
result.Should().BeOfType <NotFoundResult>();
}