public async Task ReturnsAUser()
            {
                var user = await UsersEndpoint.GetByUserId(UserId);

                Assert.NotNull(user);
                Assert.Equal(user.Id, UserId);
            }
            public async Task ReturnsNullIfNotFound()
            {
                var user = await UsersEndpoint.GetByUserId(long.MaxValue);

                Assert.Null(user);
            }