Add OpenSSF Scorecards GitHub Action
Closes #48566 

As per the linked issue, this PR adds the OpenSSF Scorecards GitHub Action, which automatically checks the repo's supply-chain security processes and reports results to the repo's Security dashboard.

I have also taken the liberty of adding a [badge][1] to the README.md displaying the project's score. This badge is strictly optional and can be easily removed, just say the word!

[1]: https://openssf.org/blog/2022/09/08/show-off-your-security-score-announcing-scorecards-badges/
@lithomas1 Done. @mroeschke I'm not sure why the CircleCI tests are failing. Seems to be missing python tests? I've noticed a few other recent PRs with the same failures (#48658, #48621), was this solved? > @mroeschke I'm not sure why the CircleCI tests are failing. Seems to be missing python tests? I've noticed a few other recent PRs with the same failures (#48658, #48621), was this solved?

Can you merge main? thanks @pnacht  This is failing on main.

Is there a quick fix? Otherwise I would propose reverting till this is fixed

https://github.com/pandas-dev/pandas/actions/runs/3092278697/jobs/5003363101 Yes, this should be quick to fix. Many apologies! I'll write a new PR with a fix in a few minutes. @phofl Submitted the PR fixing this #48668. Truly sorry, my apologies!