Update canonical datasets using a webhook
Webhook invalidation of canonical datasets (GitHub):
  - [x] setup the [`revision` argument](https://huggingface.co/docs/datasets/package_reference/loading_methods.html#datasets.load_dataset) to download datasets from the master branch - #119 
  - [x] set up a webhook on `datasets` library on every push to the master branch - see https://github.com/huggingface/moon-landing/issues/1345 - not needed anymore because the canonical datasets are mirrored to the hub.
  - [x] add an endpoint to listen to the webhook
  - [x] parse the webhook to find which caches should be invalidated (creation, update, deletion)
  - [x] refresh these caches
Update canonical datasets using a webhook: Webhook invalidation of canonical datasets (GitHub):
  - [x] setup the [`revision` argument](https://huggingface.co/docs/datasets/package_reference/loading_methods.html#datasets.load_dataset) to download datasets from the master branch - #119 
  - [x] set up a webhook on `datasets` library on every push to the master branch - see https://github.com/huggingface/moon-landing/issues/1345 - not needed anymore because the canonical datasets are mirrored to the hub.
  - [x] add an endpoint to listen to the webhook
  - [x] parse the webhook to find which caches should be invalidated (creation, update, deletion)
  - [x] refresh these caches