private FutureRecordMetadata appendToAccumulator(TopicPartition tp) throws InterruptedException {
        return appendToAccumulator(tp, time.milliseconds(), "key", "value");
    }
Test the scenario that FetchResponse returns NOT_LEADER_OR_FOLLOWER, indicating change in leadership, along with
new leader info(defined in KIP-951).
clients/src/test/java/org/apache/kafka/clients/producer/internals/SenderTest.java