public static boolean isContent(ServiceType serviceType) {
        return ServiceType.DISTRIBUTOR.equals(serviceType) ||
                ServiceType.SEARCH.equals(serviceType) ||
                ServiceType.STORAGE.equals(serviceType);
    }
@return true iff the service type refers to a content service cluster.
orchestrator/src/main/java/com/yahoo/vespa/orchestrator/model/VespaModelUtil.java