Clarify 404 access guidance in errors (#4010)
* fix(errors): clarify private repo access guidance
* Update upload_folder 404 docstring guidance
Co-authored-by: célina <hanouticelina@users.noreply.github.com>
* Apply suggestions from code review
Co-authored-by: célina <hanouticelina@gmail.com>
* Update src/huggingface_hub/cli/_errors.py
---------
Co-authored-by: Cursor Agent <cursoragent@cursor.com>
Co-authored-by: célina <hanouticelina@users.noreply.github.com>
Co-authored-by: célina <hanouticelina@gmail.com>
