Authenticated users without an email address do not get notifications

[ebouaziz@…]

This is a regression introduced in #12658

in mail.py in the match_recipient() function in RecipientMatcher :

before #12658, a user with no email address would not appear in self.email_map and use_short_addr or smtp_default_domain options would be applied.

Now, any authenticated user in the database will appear in self.users so we always run the if address in self.users: branch for authenticated users and never the elif ... branch so the use_short_addr or smtp_default_domain options are never applied to these users.