Use /users endpoint for leaderboard

[gracewzhang]

Description

• Modify the leaderboard so that it uses real user data instead of dummy data

Todo

These points are a rough guideline. Please feel free to explore what the best way to design this feature is!

• Check out the /users endpoint in the API <-- this is what you'll be calling from the frontend to get a list of all users & their relevant stats
• Inside the page containing the Leaderboard component, use useQuery() to call /users & retrieve the list of users
  • The nice thing abt the endpoint is that the list it returns is automatically sorted by points!
  • You can reference the check in page for an example of how to use useQuery()
• Replace the dummy data w/the list returned by your API call

Useful links

• React query queries