refactor: redirect page in the frontend

[kayra1]

Description

This PR moves the redirect mechanism from the backend to the frontend, which is a bit cleaner and fixes a bug where any url that ends with a slash (like /users/ or /alkshflgeh/) redirects to the certificate_requests page.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that validate the behaviour of the software
• I validated that new and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules