FEATURE: UX improvements to leaderboard page

[github-actions[bot]]

User Story

• As a user
• the leaderboard UI is improved
• So that I can navigate the app more easily.

Acceptance Criteria

• [x] Move the "back" button to the top of the page
• [x] Remove the columns labeled userCommons Id and User Id
• [x] Change the label on the name column from Username to Farmer
• [x] Right justify the numbers in the columns Cows Owned, Cow Health, Cows Bought, Cows Sold, and Cow Deaths

Implementation Todos

Hint: look at how the Create Restaurant button was placed in team03 for a hint on how to place the button in that position on the page.