private Set<Version> keepMajorVersion(int majorVersion, Set<Version> versions) {
        return versions.stream().filter(v -> v.getMajor() == majorVersion).collect(Collectors.toSet());
    }
Allow build of other config models to fail if there is a validation override that allow skipping old
config models, or we're manually deploying
configserver/src/main/java/com/yahoo/vespa/config/server/modelfactory/ModelsBuilder.java