public async Task GetMainCategegoryIdBySubCategoryId_ThrowsExceptionIfIdIsNull()
{
var context = ApplicationDbContextInMemoryFactory.InitializeContext();
var subCategoryRepository = new EfDeletableEntityRepository <SubCategory>(context);
var subCategoryService = new SubCategoryService(subCategoryRepository);
await Assert.ThrowsAsync <ArgumentNullException>(async() =>
{
await subCategoryService.GetMainCategoryNameBySubCategoryId(null);
});
}