code: public function removeSubscriberInterface(SubscriberInterface $interface)
      {
          $subscribers = $this->getInterfaceSubscribers($interface);
          foreach ($subscribers as $row) {
              $this->unsubscribe($row[0], $row[1], $row[2]);
          }
          return $subscribers;
      }
docs: Unsubscribe from all of the event subscribers defined in passed obj
  
  @param SubscriberInterface $interface object implementing subscriber interface
  
  @return array a normalized list of subscriptions removed.
  each returned is array(eventName, callable, priority)