Show license for yanked Python packages for exact version matches

[pilosus]

It's correct to ignore yanked Python packages when there's no version specified expression or we use <, '>' or their variations with =. But in case of exact matching, we need to show the license, e.g.

grpcio==1.48.0

should show the license, rather than PyPI::version Not found.
We can also save time on fetching versions from PyPI Simple API for exact matching: no need to do two requests, as a request for JSON API will do.