docs: public void saveReplyMessageChannel(Message receivedMessage, TestContext context) {
          MessageChannel replyChannel = null;
          if (receivedMessage.getHeader(org.springframework.messaging.MessageHeaders.REPLY_CHANNEL) instanceof MessageChannel) {
              replyChannel = (MessageChannel)receivedMessage.getHeader(org.springframework.messaging.MessageHeaders.REPLY_CHANNEL);
          } else if (StringUtils.hasText((String) receivedMessage.getHeader(org.springframework.messaging.MessageHeaders.REPLY_CHANNEL))) {
              replyChannel = resolveChannelName(receivedMessage.getHeader(org.springframework.messaging.MessageHeaders.REPLY_CHANNEL).toString(), context);
          }
  
          if (replyChannel != null) {
              String correlationKeyName = endpointConfiguration.getCorrelator().getCorrelationKeyName(getName());
              String correlationKey = endpointConfiguration.getCorrelator().getCorrelationKey(receivedMessage);
              correlationManager.saveCorrelationKey(correlationKeyName, correlationKey, context);
              correlationManager.store(correlationKey, replyChannel);
          } else {
              log.warn("Unable to retrieve reply message channel for message \n" +
                      receivedMessage + "\n - no reply channel found in message headers!");
          }
      }