Fix list() and help() torchhub functions for Windows (#63773)
Summary:
This PR Fixes the help() and list() torchhub functions which were probably failing for Windows since the `/` OS separator was hardcoded.
Before merging this I need to double check whether the CI actually runs the corresponding tests on Windows or not
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63773
Reviewed By: zou3519
Differential Revision: D30695664
Pulled By: NicolasHug
fbshipit-source-id: fac328163fd05db804a8186ae28f22b3cc3a6404
