public async void RatingRepository_Post_NullRating_Failure()
{
RatingEntry _rating = null;
_mockContext.Setup(p => p.RatingsCollectionName).Returns("ratings");
_mockContext.Setup(p => p.ConnectionString).Returns("mongodb://localhost:27017");
_mockContext.Setup(p => p.DatabaseName).Returns("RatingDB");
var ratingRepository = new RatingRepository(_mockContext.Object);
await Assert.ThrowsAsync <ArgumentNullException>(() => ratingRepository.AddRating(_rating));
}
