Add wins event type to Whiteboard

Labs is amazing. We should celebrate our wins more. This change aims to give people a well-defined venue to tell their peers about their successes, let us all applaud, and give everyone a nice high point to start their day.

It is last in the list of standup items to give everyone a happy point to start their day on. I intend for the tradition to be a brief round of applause for each win.