fix: make the open graph image use a favicon from the site

the url that was used no longer exists, and I think it's probably
better to just stick to our own images and stuff that are
readily available.
3 jobs for master in 2 minutes and 22 seconds (queued for 1 second)
latest
Status Job ID Name Coverage
  Test
passed #633403173
lint

00:01:19

 
  Deploy
passed #633403182
pages

00:01:02

passed pages:deploy

00:00:03