Skip tests relying on RepoNotFound errors until bug is fixed
# What does this PR do?

There is an (hopefully temporary) bug on the Hub right now not returning the `RepoNotFoundError` when someone tries to hit a wrong repo. This PR skips all the tests relying on it until the bug is fixed so the main branch stays green and community contributors don't start getting strange errors.

Will merge as soon as it's green.
_The documentation is not available anymore as the PR was closed or merged._