Clear PR merge commit description field

[fregante]

On PRs, when squashing, the commit description is filled with every commit's title.

I think that if you squash, probably aren't interested in every commit's title and should therefore be dropped. If they're useful, maybe you should merge or rebase instead, IMHO.

Thoughts?

Perhaps we should just preserve a deduplicated list of Co-authored-by

Currently

Expected

[sindresorhus]

I sometimes find it useful to be able to quickly scan what commits are included in the squash and I do think we should preserve a deduplicated list of co-authors. How about we present a list of commit titles underneath or something? So I can still scan it, but it's not included by default.