[Unfork] Improve UI that links to GitHub docs on restoring deleted projects

Description

As Unfork doesn't provide a backup script (#9 is not done yet), users may not know how to restore their deleted projects. Hence, we should add a UI that gives users information on how to restore their projects.

Suggested solution

• UI should be a button with "?" symbol, and a text like "Restoring deleted repos".
• Upon click, this button redirects user in a new tab to https://docs.github.com/en/repositories/creating-and-managing-repositories/restoring-a-deleted-repository
• Placement of this UI should be at the history page, file: /Unfork/history.tsx
• Alternative proposals are welcome as long they look nice, accessible and make sense