public void poll(long timeout, Supplier<UncheckedCloseable> onPoll) {
        if (timeout < 0)
            throw new IllegalArgumentException("Timeout must not be negative");
        coordinator.poll(timeout, onPoll);
    }
Ensure that the connection to the broker coordinator is up and that the worker is an
active member of the group.
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/distributed/WorkerGroupMember.java