Add section about deprecation of script-based datasets?

[severo]

Asked here: https://github.com/huggingface/datasets-server/issues/2385#issuecomment-2017984722

Perhaps a little bit of suggestion from me is to include a disclaimer in the docs so that others are aware that developing a custom script is not supported.

It would also help answer the discussions + we could link in the error message directly.

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On the other hand, maybe we just want to deprecate it sooner than later, and not spend too much time on this.

[severo]

cc @lhoestq ?

[lhoestq]

They're not "deprecated" since we'll keep supporting them in datasets, they're rather "unsupported for the Viewer".

Maybe we should mention it here ? https://huggingface.co/docs/hub/datasets-viewer

[julien-c]

for me if you require TRUST_REMOTE_CODE=true it's kinda deprecating script-based datasets no?