public SOAPDecoder build() {
      if (jaxbContextFactory == null) {
        throw new IllegalStateException("JAXBContextFactory must be non-null");
      }
      return new SOAPDecoder(this);
    }
Alters the behavior of the code to use the {@link SOAPBody#getFirstChild()} in place of
{@link SOAPBody#extractContentAsDocument()}.

@return the builder instance.
soap-jakarta/src/main/java/feign/soap/SOAPDecoder.java