Add option for X/X users approved on main UI

[JoshuaAshdown]

Our team requires 2 reviews, one from a peer, and one from a lead, and we use two groups to do that, LeadDevs + Contributors, the problem is in the edge case where a LeadDev approves first, it ticks both groups, hiding visibility on when a peer needs to do a review.

An easy way to alleviate this issue, would be if the number of reviewers left to review could be made more prominent on the hub UI. Others may not want this so having it as a toggleable option in the preferences menu seems like a sensible choice.