Memory intensive repository method, `findEnabled`

[loevgaard]

We need to look into this method:

https://github.com/Setono/SyliusGiftCardPlugin/blob/v0.11.9/src/Doctrine/ORM/GiftCardRepository.php#L57-L62

• where is it used?
• what can we do to not use it?

because this would be very memory intensive for say 100,000 enabled gift cards

Probably related: #148