public void Saml2AuthenticationRequest_ToXml_PreservesCustomChanges()
        {
            var subject = new Saml2AuthenticationRequest();

            subject.XmlCreated += (s, e) =>
            {
                e.Add(new XAttribute("CustomAttribute", "CustomValue"));
            };

            var xml = subject.ToXml();

            xml.Should().Contain("CustomAttribute=\"CustomValue\"");
        }