Add links / info about existing usages

[coyotte508]

For now:

• used internally on hf.co for a cool upcoming feature (to be revealed)
• used in a github action to deploy a space: https://github.com/gradio-app/github/tree/main/packages/deploy-space cc @pngwn
• used in a github action in Deno to delete old files from a repo: https://github.com/huggingface/doc-builder/blob/main/scripts/delete-old-prs.ts
• used soon in a cool ML app (to be revealed)
• https://hpssjellis.github.io/my-examples-of-huggingfacejs/public/index.html

overlaps with #57

[julien-c]

• used to publish a model from a webpage, using user's inputted token: https://huggingface.co/spaces/julien-c/push-model-from-web

[coyotte508]

https://github.com/huggingface/zapier - zapier integration