protected synchronized boolean rejoinNeededOrPending() {
        // if there's a pending joinFuture, we should try to complete handling it.
        return rejoinNeeded || joinFuture != null;
    }
Check whether the group should be rejoined (e.g. if metadata changes) or whether a
rejoin request is already in flight and needs to be completed.

@return true if it should, false otherwise
clients/src/main/java/org/apache/kafka/clients/consumer/internals/AbstractCoordinator.java