Fix project transfer e-mail sending incorrect paths in e-mail notification

The introduction of ActiveJob and `deliver_now` in 7f214cee caused a race
condition where the mailer would be invoked before the project was committed
to the database, causing the transfer e-mail notification to show the old
path instead of the new one.

Closes #4670

CHANGELOG

@@ -13,6 +13,9 @@ v 8.4.0 (unreleased)
   - Revert back upvote and downvote button to the issue and MR pages
   - Enable "Add key" button when user fills in a proper key (Stan Hu)
 
+v 8.3.3 (unreleased)
+  - Fix project transfer e-mail sending incorrect paths in e-mail notification (Stan Hu)
+
 v 8.3.2
   - Disable --follow in `git log` to avoid loading duplicate commit data in infinite scroll (Stan Hu)
   - Add support for Google reCAPTCHA in user registration

app/models/project.rb

@@ -555,7 +555,9 @@ class Project < ActiveRecord::Base
   end
 
   def send_move_instructions(old_path_with_namespace)
-    NotificationService.new.project_was_moved(self, old_path_with_namespace)
+    # New project path needs to be committed to the DB or notification will
+    # retrieve stale information
+    run_after_commit { NotificationService.new.project_was_moved(self, old_path_with_namespace) }
   end
 
   def owner