Use Doctrine for the opens and clicks exporters

This commit refactors the code that handles exporting e-mails opens and
clicks when generating the personal data file to use Doctrine instead of
Paris. I opted to do this in this task as opens and clicks code share
some functionality, and I didn't want to add more code that relies on
Paris, as we are eventually going to remove it.

[MAILPOET-3738]

lib/Models/StatisticsOpens.php

@@ -2,10 +2,6 @@
 
 namespace MailPoet\Models;
 
-use MailPoet\DI\ContainerWrapper;
-use MailPoet\Entities\UserAgentEntity;
-use MailPoetVendor\Doctrine\ORM\EntityManager;
-
 /**
  * @property int $newsletterId
  * @property int $subscriberId
@@ -28,27 +24,4 @@ class StatisticsOpens extends Model {
     }
     return $statistics;
   }
-
-  public static function getAllForSubscriber(Subscriber $subscriber) {
-    $entityManager = ContainerWrapper::getInstance()->get(EntityManager::class);
-    $userAgentsTable = $entityManager->getClassMetadata(UserAgentEntity::class)->getTableName();
-
-    return static::tableAlias('opens')
-      ->select('opens.id', 'id')
-      ->select('newsletter_rendered_subject')
-      ->select('opens.created_at', 'created_at')
-      ->select('user_agent.user_agent')
-      ->join(
-        SendingQueue::$_table,
-        ['opens.queue_id', '=', 'queue.id'],
-        'queue'
-      )
-      ->leftOuterJoin(
-        $userAgentsTable,
-        ['opens.user_agent_id', '=', 'user_agent.id'],
-        'user_agent'
-      )
-      ->where('opens.subscriber_id', $subscriber->id())
-      ->orderByAsc('newsletter_rendered_subject');
-  }
 }