Since 7b4a3d4c instead of subscribing after add code unsubscribed which is…

Since 7b4a3d4c instead of subscribing after add code unsubscribed which is illogical. Revert back. Credit Kaz.

Tests passing : https://nexedi.erp5.net/test_result_module/20200327-660269E/view?ignore_layout:int=1