public void ThenItShouldReturnSoapMesage()
        {
            var actual = _builder.BuildMessageToGetUpdatesSince(_updatedSince);

            var envelope = XElement.Parse(actual);

            Assert.AreEqual("Envelope", envelope.Name.LocalName);
            Assert.AreEqual(soapNs.NamespaceName, envelope.Name.NamespaceName);

            Assert.IsNotNull(envelope.Elements().SingleOrDefault(e =>
                                                                 e.Name.LocalName == "Header" && e.Name.NamespaceName == soapNs.NamespaceName));

            Assert.IsNotNull(envelope.Elements().SingleOrDefault(e =>
                                                                 e.Name.LocalName == "Body" && e.Name.NamespaceName == soapNs.NamespaceName));
        }