docs: protected <T extends SAMLObject> void prepareSamlOutboundProtocolMessageSigningHandler(final MessageContext<T> outboundContext) throws Exception {
          LOGGER.trace("Attempting to sign the outbound SAML message...");
          val handler = new SAMLOutboundProtocolMessageSigningHandler();
          handler.setSignErrorResponses(casProperties.getAuthn().getSamlIdp().getResponse().isSignError());
          handler.invoke(outboundContext);
          LOGGER.debug("Signed SAML message successfully");
      }