Make RapidOcrOptions ignore `artifacts_path`

### Requested feature
Currently, when using RapidOCR, the initialization of `RapidOcrModel` considers `artifacts_path`. That is, it searches for model artifacts under `artifacts_path` as defined here:
- https://github.com/docling-project/docling/blob/6a04e273528691eb22a5708f1270d4c5fa8f5b7c/docling/models/auto_ocr_model.py#L65-L74
- https://github.com/docling-project/docling/blob/6a04e273528691eb22a5708f1270d4c5fa8f5b7c/docling/models/rapid_ocr_model.py#L125-L149

When installing `rapidocr` it already ships with the base onnx models available under `...\Lib\site-packages\rapidocr\models`. Therefore, we usually do not need downloading these models separately from Modelscope. However, when setting `artifacts_path` in the pipeline, e.g., for loading the layout detection or table structure model, we are currently not able to load the default onnx models shipped with `rapidocr`.

@geoHeil Would it be possible to either deliberately skip a globally defined `artifacts_path` in order to preload the shipped models and skip downloading from Modelscope or b) make loading from `...\Lib\site-packages\rapidocr\models` the default?