@Override
        @SuppressWarnings("unchecked")
        public void onSuccess(ClientResponse clientResponse, RequestFuture<T> future) {
            try {
                this.response = clientResponse;
                R responseObj = (R) clientResponse.responseBody();
                handle(responseObj, future);
            } catch (RuntimeException e) {
                if (!future.isDone())
                    future.raise(e);
            }
        }
Sends LeaveGroupRequest and logs the {@code leaveReason}, unless this member is using static membership or is already
not part of the group (ie does not have a valid member id, is in the UNJOINED state, or the coordinator is unknown).

@param leaveReason the reason to leave the group for logging
@throws KafkaException if the rebalance callback throws exception
clients/src/main/java/org/apache/kafka/clients/consumer/internals/AbstractCoordinator.java