Only comment with collapsed details (#6972)
Only comment with collapsed details (#6972)

Summary:
The Marathon CI bot would approve or reject pull requests and spam the
comments section. This change remove the bot as an approve and thus
enforce the two-approval rule. It also changes a big protion of the
comments to a details field and slims down the noise.

mesosphere/marathon,mesosphere/marathon,mesosphere/marathon,mesosphere/marathon,mesosphere/marathon