[DO NOT MERGE] Test doc-builder with skipped installation feature
_The documentation is not available anymore as the PR was closed or merged._ Fix in https://github.com/huggingface/doc-builder/pull/162 works as expected (docs build), closing this
This PR is just for testing that we can build PR docs with changes made on the [`skip-install-for-real`](https://github.com/huggingface/doc-builder/tree/skip-install-for-real) branch of `doc-builder`.