docs: public static String parseMessagePayload(Element payloadElement) {
          if (payloadElement == null) {
              return "";
          }
          
          try {
              Document payload = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument();
              payload.appendChild(payload.importNode(payloadElement, true));
  
              String payloadData = XMLUtils.serialize(payload);
              // temporary quickfix for unwanted testcase namespace in target payload
              payloadData = payloadData.replaceAll(" xmlns=\\\"http://www.citrusframework.org/schema/testcase\\\"", "");
              return payloadData.trim();
          } catch (DOMException e) {
              throw new CitrusRuntimeException("Error while constructing message payload", e);
          } catch (ParserConfigurationException e) {
              throw new CitrusRuntimeException("Error while constructing message payload", e);
          }
      }