Support for newer versions of JAX
### Feature request

Hi,

I like your idea of adapting the datasets library to be usable with JAX. Thank you for that.

However, in your [setup.py](https://github.com/huggingface/datasets/blob/main/setup.py), you enforce old versions of JAX <= 0.3... It is very cumbersome !

What is the rationale for such a limitation ? Can you remove it please ?

Thanks,

### Motivation

This library is unusable with new versions of JAX ?

### Your contribution

Yes.