refactor #310 Replace deprecated twig extension (Tomanhez)

This PR was merged into the 1.0-dev branch.

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79c3db2 Replace deprecated twig extension

src/Twig/OrderRefundsExtension.php

@@ -20,9 +20,10 @@
 use Sylius\RefundPlugin\Model\RefundType;
 use Sylius\RefundPlugin\Provider\OrderRefundedTotalProviderInterface;
 use Sylius\RefundPlugin\Provider\UnitRefundedTotalProviderInterface;
+use Twig\Extension\AbstractExtension;
 use Twig\TwigFunction;
 
-final class OrderRefundsExtension extends \Twig_Extension
+final class OrderRefundsExtension extends AbstractExtension
 {
     /** @var OrderRefundedTotalProviderInterface */
     private $orderRefundedTotalProvider;