Json builder: Allow features to override problematic Arrow types
Hi ! It would be cool indeed, currently the JSON data are generally loaded here: 

https://github.com/huggingface/datasets/blob/90e5bf8a8599b625d6103ee5ac83b98269991141/src/datasets/packaged_modules/json/json.py#L137-L140

Maybe we can pass a Arrow `schema` to avoid errors ?
### Feature request

In the JSON builder, use explicitly requested feature types before or while converting to Arrow.

### Motivation

Working with JSON datasets is really hard because of Arrow.  At the very least, it seems like it should be possible to work-around these problems by explicitly setting problematic columns's types.  But it seems like this is not possible because the features are only used *after* converting to arrow.

Here's a simple example where the Arrow error could potentially be avoided by converting the column to a string: https://colab.research.google.com/drive/16QHRdbUwKSrpwVfGwu8V8AHr8v2dv0dt?usp=sharing

### Your contribution

Maybe with some guidance.  I'm not very familiar with arrow or pandas.