public void GetUserNotificationFor_ValidIdUnread_ShouldReturn()
        {
            var user = new ApplicationUser()
            {
                Id = "1"
            };

            var userNotification = new UserNotification(user, Notification.AppointmentCreated(new Appointment()));

            _mockUserNotification.SetSource(new[] { userNotification });

            _mockContext.SetupGet(c => c.UserNotifications).Returns(_mockUserNotification.Object);

            var result = _repository.GetUserNotificationsFor(user.Id);

            result.Should().Contain(userNotification);
            result.Count().Should().Be(1);
        }