Add regex syntax info below the URI settings

Whenever I want to use a regex for the URI pattern, I always have to look up how bitwarden processes forward slashes. Some programs need them to be escaped. Some don’t.

It would be nice if this information at the bottom of the screen shot said something about not needing to escape forward slashes. That way I could rule that out as one of the reasons why my regex didn’t work the way I expected.