public void SendNewSessionRequestDoesNotAppendIfAdditionalQueryParametersAreNull()
        {
            // given
            string capturedUrl = null;

            spyClient.DoGetRequest(Arg.Do <string>(u => capturedUrl = u), Arg.Any <string>())
            .Returns(CreateSuccessHttpResponse());

            // when
            spyClient.SendNewSessionRequest(null);

            // then
            var expectedUrl = InitializeBaseUrl();

            AppendUrlParameter(expectedUrl, "ns", "1");
            Assert.That(capturedUrl, Is.EqualTo(expectedUrl.ToString()));
        }