public void UserRegistration_ReturnOKResult()
        {
            var details = new UserDetail()
            {
                UserName = "******",
                Email    = "*****@*****.**",
                Password = "******",
                UserType = "Security"
            };

            var okResult = registrationController.AddUser(details);

            // Assert
            Assert.IsType <OkObjectResult>(okResult);
        }