public async Task GetArtistSongsStats_WhenArtistNameIsEmpty_ShouldReturnBadRequest()
{
_artistServiceMock.Setup(_ => _.GetArtistSongsStats(It.IsAny <string>())).Returns(Task.FromResult(new ArtistSongsStats()));
var response = await _artistController.GetArtistSongsStats("");
response.Should().BeOfType <BadRequestObjectResult>();
}