private List<NamedReader> asNamedReaderList(String value) {
        if (value == null) return List.of();
        return List.of(new NamedReader(extractId(value) + ".xml", new StringReader(value)));
    }
Additional (mock) files that will exist in this application package, with their content.
config-model/src/main/java/com/yahoo/config/model/test/MockApplicationPackage.java