Fixes and details to torchhub docs (#63783)
Summary:
This PR:
- adds a few details regarding the newly added `skip_validation` parameter https://github.com/pytorch/pytorch/pull/62139
- uses double-backticks instead of single-backticks since this is rst, not mardown.
- adds a few minor doc nits here and there
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63783
Reviewed By: zou3519
Differential Revision: D30696658
Pulled By: NicolasHug
fbshipit-source-id: 6f01c7eb3cfcd7e17e4c33c09d193054fa18ad36
