public void exportOnnxModels(String toDirectory) throws IOException {
        var b = new OnnxModelsConfig.Builder()
                .model(rankProfileList.getOnnxConfig());
        exportCfg(b.build(), toDirectory + "/" + "onnx-models.cfg");
    }
Exports a complete set of configuration-server format config files.

@param toDirectory  the directory to export to, current dir if null
@throws IOException if exporting fails, some files may still be created
config-model/src/main/java/com/yahoo/schema/derived/DerivedConfiguration.java