public void maybeRejoinStaleMember() {
        isPollTimerExpired = false;
        if (state == MemberState.STALE) {
            log.debug("Expired poll timer has been reset so stale member {} will rejoin the group" +
                    "when it completes releasing its previous assignment.", memberId);
            transitionToJoining();
        }
    }
@return True if the member is preparing to leave the group (waiting for callbacks), or
leaving (sending last heartbeat). This is used to skip proactively leaving the group when
the consumer poll timer expires.
clients/src/main/java/org/apache/kafka/clients/consumer/internals/ShareMembershipManager.java