since 99% of the time it's `target.project` anyways.

since it's only called once now in make_recipient

its functionality is swept into the project permission check
in NotificationRecipient#has_access? now

it's not there in the case of personal snippets, f. ex., and we've
already guarded against its being missing in #find_notification_setting

to get a pipeline_failed email

to get pipeline failed notifications