code: public static void transmit(TracingSetter tracingSetter) {
          if (TracingContext.tracing().hasGroup()) {
              log.debug("tracing transmit group:{}", TracingContext.tracing().groupId());
              tracingSetter.set(TracingConstants.HEADER_KEY_GROUP_ID, TracingContext.tracing().groupId());
              tracingSetter.set(TracingConstants.HEADER_KEY_APP_MAP,
                      Base64Utils.encodeToString(TracingContext.tracing().appMapString().getBytes(StandardCharsets.UTF_8)));
          }
      }
docs: 传输Tracing信息
  
  @param tracingSetter Tracing信息设置器