Update Actions file so that PRs are deployed to a subdomain

[gunr2171]

Right now, when a PR is submitted, Contributors to this repo have no way of knowing what the final deployed website will look like. It would be great to have PR deploy to "test.socvr.org" (or some other subdomain). Of course, only Contributors should be able to authorize a PR (even if the PR was not authored by a Contributor) to deploy to the subdomain - this will avoid spam.

I, personally, don't know how to do this. @ccharles this is where you come in if you'd like.

[ccharles]

Thanks @gunr2171. I'll start digging into the open issues this weekend.