tell user how to paste token on Windows

[fristhon]

getpass() can't handle Ctrl+V on Windows which causes "invalid token error" in VSCode and CMD
https://bugs.python.org/issue37426

This causes confusion for the user, actually happened to me several times! so I decided to send this PR for a better UX.

[Wauplin]

Hi @fristhon , thanks for your input and for taking the time to make a PR for it. I approved it and will soon merge it :)

(note: I've updated the PR to use os.name == "nt" instead of sys.platform.startswith("win"). It's not better or worse, just more consistent with the existing codebase)

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.