public void GetAllUsers_WithUsersInDb_ReturnsAllUsers()
        {
            var guidId  = Guid.NewGuid().ToString();
            var guidId2 = Guid.NewGuid().ToString();
            var user    = new User()
            {
                Id = guidId, FirstName = "test", LastName = "test", Email = "*****@*****.**", UserName = "******", RegistrationDate = DateTime.Now, LockoutEnd = DateTime.Now.AddDays(-2)
            };
            var user2 = new User()
            {
                Id = guidId2, FirstName = "test2", LastName = "test2", Email = "*****@*****.**", UserName = "******", RegistrationDate = DateTime.Now.AddDays(1), LockoutEnd = DateTime.Now.AddDays(2)
            };

            context.Add(user);
            context.Add(user2);
            context.SaveChanges();

            var result = this.userService.GetAllUsers();

            Assert.IsNotNull(result);
            Assert.AreEqual(2, result.Count);
        }