Add OpenSSF score

[ljharb]

Using this workflow: https://github.com/marketplace/actions/ossf-scorecard-action i suspect we can extract a command, so we could provide the score for every repo.

if the computation is expensive, then we may want to consider making this score be opt-in instead of visible by default, and we may want aggressive caching.

[Riyabelle25]

Hiya @ljharb
As per our discussion in the last Maintainer's call, I'll be trying my hand at this

[Riyabelle25]

Heya @ljharb
As promised, here are the code changes that implement openssf in repo-report.
I tried to make it as neat as possible- lemme know what possible direction we can take from here