2024q2 report: fix github report markup

The bullet list wasn't rendering properly, so fix that. Also, although
done in the first week of july, we can now do multiple pull requests in
one staging branch for CI batch testing, so add that to what we've done,
turning that into a bullet list as well. Tweak the lists a little to
tighten them up. Add encouragement to join us after telling people
where.

Noticed by: graham perrin (bullet markup)
Sponsored by: Netflix