public Stream<ConfigChangeAction> findServicesWithChangedStartupCommand(AbstractConfigProducerRoot currentModel,
                                                                            AbstractConfigProducerRoot nextModel) {
        return nextModel.getDescendantServices().stream()
                .map(nextService -> currentModel.getService(nextService.getConfigId())
                                                .flatMap(currentService -> compareStartupCommand(currentService, nextService)))
                .filter(Optional::isPresent)
                .map(Optional::get);
    }
Compares the startup command for the services in the next model with the ones in the current model.
If the startup command has changes, a change entry is created and reported back.

@author bjorncs
config-model/src/main/java/com/yahoo/vespa/model/application/validation/change/StartupCommandChangeValidator.java