Links in signup form don't work

Steps to reproduce

1. Create a signup form
2. Add a markdown link using []() syntax
3. Save the form
4. Navigate to the /signup page

What happens?

The link renders as a link, but it's not actually interactive. Clicking it doesn't take the user anywhere.

What is expected?

The link should take the user straight to the linked page.

Context

Funkwhale version(s) affected: 1.2.8+git.e3c81ca3