Add Github / Netlify Actions to deploy PRs

[Korusuke]

It would be great to deploy PRs so that it's easy to review / test them, this deployments links can be commented in the PR itself.

https://docs.netlify.com/site-deploys/notifications/#github-pull-request-comments

[wrussell1999]

I actually added Netlify this morning! There’s one issue though: it breaks because of the github pages site being hosted on /portfolio-site

[jkmartindale]

There’s one issue though: it breaks because of the github pages site being hosted on /portfolio-site

If it helps, I got a working deployment at https://agitated-davinci-5178e1.netlify.app/ with a corresponding netlify.toml. My build config does 3 things:

• Set _site as the publish directory so Netlify doesn't serve raw templates
• Install nokogiri before everything else, because for some reason that fixes issues I ran across when I added github-pages (to keep environments consistent)
• Hacky build-time config file generation that overrides the URL structure to match deployment URL