FEATURE: ADD upcoming events section to our website landing page

[lwasser]

Right now, we have an events page here

https://www.pyopensci.org/events.html

Let's add a breakout to our home page that has "upcoming events". The section should only render if we have events to show.

It might make sense for this to go below new contribitors. and if there are no upcoming events, we can hide the block. We don't always have events.