private OffsetCommitCallback callback(final AtomicBoolean success) {
        return (offsets, exception) -> {
            if (exception == null)
                success.set(true);
        };
    }
Verifies that subscription change updates SubscriptionState correctly even after JoinGroup failures
that don't re-invoke onJoinPrepare.
clients/src/test/java/org/apache/kafka/clients/consumer/internals/ConsumerCoordinatorTest.java