Apply safe to load association trait to all toOne associations

[MAILPOET-2818]

lib/Entities/StatsNotificationEntity.php

@@ -4,6 +4,7 @@ namespace MailPoet\Entities;
 
 use MailPoet\Doctrine\EntityTraits\AutoincrementedIdTrait;
 use MailPoet\Doctrine\EntityTraits\CreatedAtTrait;
+use MailPoet\Doctrine\EntityTraits\SafeToOneAssociationLoadTrait;
 use MailPoet\Doctrine\EntityTraits\UpdatedAtTrait;
 use MailPoetVendor\Doctrine\ORM\Mapping as ORM;
 
@@ -15,6 +16,7 @@ class StatsNotificationEntity {
   use AutoincrementedIdTrait;
   use CreatedAtTrait;
   use UpdatedAtTrait;
+  use SafeToOneAssociationLoadTrait;
 
   /**
    * @ORM\OneToOne(targetEntity="MailPoet\Entities\NewsletterEntity")
@@ -37,6 +39,7 @@ class StatsNotificationEntity {
    * @return NewsletterEntity
    */
   public function getNewsletter() {
+    $this->safelyLoadToOneAssociation('newsletter');
     return $this->newsletter;
   }
 
@@ -44,6 +47,7 @@ class StatsNotificationEntity {
    * @return ScheduledTaskEntity
    */
   public function getTask() {
+    $this->safelyLoadToOneAssociation('task');
     return $this->task;
   }
 }