Remove the unit test checking if purple_contact_info_matches can match an id

Originally we had purple_contact_info_matches checking id's for stuff like IRC,
but for protocols that use UUID's you start getting weird matches if because
searching for `af` can very easily match a UUID and isn't what the user would
expect.

Testing Done:
Ran the unit tests and verified they pass again.

Reviewed at https://reviews.imfreedom.org/r/2241/