private FileReference resolvePath(String value) {
        Path path = pathAcquirer.getPath(new FileReference(value));
        return new FileReference(path.toString());
    }
This may run on both the config server and subscribing nodes.
We only have a urlDownloader set up when client side.
config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java