Add CrossEncoder to the Sentence Transformers "How to Use" snippet & patch SetFit

[tomaarsen]

Hello!

Pull Request overview

• Add CrossEncoder to the Sentence Transformers "How to Use" snippet
• Patch "How to Use" for SetFit models (that are also tagged as Sentence Transformers)

Details

This PR adds the CrossEncoder class to the "How to Use" snippets. I'm working on feature parity of these models with the more common SentenceTransformer models, and the recent Sentence Transformers v4.0 release was a big step in that.
We're already at 150 models: https://huggingface.co/models?pipeline_tag=text-ranking&library=sentence-transformers

Beyond that, this ensures that [widgetExample.source_sentence, ...widgetExample.sentences] doesn't crash, apparently that currently happens for some SetFit models, e.g.: https://huggingface.co/faodl/setfit-paraphrase-mpnet-base-v2-5ClassesDesc-multilabel-augmented?library=sentence-transformers

• Tom Aarsen

[julien-c]

lgtm from a superficial glance at the code, but also cc @Wauplin 😁

[tomaarsen]

@Wauplin could you have a quick look at this? 🤗 Would like to get this out soon.

• Tom Aarsen

[Wauplin]

Looks good!

[Wauplin]

@tomaarsen I merged the PR and made a release of @huggingface/tasks. It should arrive in moon-landing by tomorrow by the dependabot (you can open a PR if you want to fast-track it).

[tomaarsen]

Thanks @Wauplin! I'll let the dependabot take care of it. I appreciate it!

• Tom Aarsen