Add cron worker for reporting subscriber stats

[MAILPOET-3868]

lib/Cron/Workers/WorkersFactory.php

@@ -122,4 +122,9 @@ class WorkersFactory {
   public function createReEngagementEmailsSchedulerWorker() {
     return $this->container->get(ReEngagementEmailsScheduler::class);
   }
+
+  /** @return SubscribersStatsReport */
+  public function createSubscribersStatsReportWorker() {
+    return $this->container->get(SubscribersStatsReport::class);
+  }
 }