public ConsumerRecords<K, V> poll(Duration timeout) {
    return poll(delegate.poll(timeout));
  }
@Test void should_add_new_trace_headers_if_b3_missing() {
    consumer.addRecord(consumerRecord);

    Consumer<String, String> tracingConsumer = kafkaTracing.consumer(consumer);
    ConsumerRecords<String, String> poll = tracingConsumer.poll(10);

    assertThat(poll)
      .extracting(ConsumerRecord::headers)
      .flatExtracting(KafkaTest::lastHeaders)
      .extracting(Map.Entry::getKey)
      .containsOnly("b3");

    MutableSpan consumerSpan = spans.get(0);
    assertThat(consumerSpan.kind()).isEqualTo(CONSUMER);
    assertThat(consumerSpan.parentId()).isNull();
  }