Revert "Skip tests relying on RepoNotFound errors until bug is fixed"
Reverts huggingface/transformers#17646

Test will fail for now, but one day, a hero will fix them and we can click the "Relaunch workflow from failed" button to see them passing, and we will be able to be merge this PR.
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_17647). All of your documentation changes will be reflected on that endpoint.