Implement leaderboard for displaying members with the most points

[gracewzhang]

• Thinking points: Where should this leaderboard live? Should it take up an entire page? What should it look like? How many members should be displayed in it? What information about each member in the leaderboard should be included? Is there a way for the user to see where they are in the leaderboard?
• Currently thinking that we can modify the /users endpoint for sorting & use react query to cache the results