GH action to update future-publish date posts, /events to sort what events are upcoming vs. past

[amandavisconti]

GH Actions allows triggering a daily rebuild, which would handle moving past events out of upcoming events: https://stackoverflow.com/questions/24098792/how-to-force-github-pages-build/61706020#61706020

1. Rebuilds /events by date so that today's and upcoming events are at top, past events are at bottom of page
2. Allow people to save posts with future publication dates, and trigger the site to rebuild on that pub date so the post becomes visible then. (Note I don't think we need the "draft" part of these workflows.)

https://thedavecarroll.com/blog/publish-post-jekyll-on-a-schedule/
https://www.bobbyowolabi.com/2022/02/07/schedule-jekyll-posts-with-github
https://soywiz.com/autopublish-jekyll-drafts