Fix unit tests [MAILPOET-903]

lib/API/JSON/v1/Newsletters.php

@@ -166,7 +166,7 @@ class Newsletters extends APIEndpoint {
     // if there are past due notifications, reschedule them for the next send date
     if($newsletter->type === Newsletter::TYPE_NOTIFICATION && $status === Newsletter::STATUS_ACTIVE) {
       $next_run_date = Scheduler::getNextRunDate($newsletter->schedule);
-      $newsletter->queue()->task()
+      $newsletter->queue()->findOne()->task()
         ->whereLte('scheduled_at', Carbon::createFromTimestamp(current_time('timestamp')))
         ->where('status', SendingQueue::STATUS_SCHEDULED)
         ->findResultSet()

lib/API/JSON/v1/SendingQueue.php

@@ -46,7 +46,7 @@ class SendingQueue extends APIEndpoint {
     }
 
     // add newsletter to the sending queue
-    $queue = SendingQueueModel::findTaskByNewsletterId($newsletter->id)
+    $queue = SendingQueueModel::joinWithTasks()
       ->whereNull('tasks.status')
       ->findOne();