Add example for BERT sequence classification

[victor23k]

Hello! :heart: the library, I'm using it right now to run inference on a BERT fine-tuned for sequence classification.

@mortont do you think it would be helpful to add an example on how to set up the pipeline for inference similar to the StableLM example? The main thing that I did not find documented anywhere (maybe I didn't looked hard enough) was getting the id2label mappings from the generated config.json. If you think it will add value, I'll prepare the PR.

[mortont]

Thanks for the feedback! Yes a PR would definitely be welcome, anything you found undocumented along the way could help others get started.