public void GetExamById_ShouldThrowExamNotFoundException()
        {
            // Arrange
            Guid mockGuid = new Guid();

            _mockReadRepository.Setup(repo => repo.GetByIdAsync <Domain.Entities.Exam>(mockGuid)).Throws(new ExamNotFoundException(mockGuid));
            // Act
            Func <Task> act = async() => await _examService.GetById(mockGuid);

            // Assert
            act.Should().Throw <ExamNotFoundException>();
        }