[validator] Fix deprecation

Author: nicolas-grekas

Tests/Constraints/ExpressionLanguageSyntaxValidatorTest.php

@@ -14,14 +14,15 @@
 use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
 use Symfony\Component\Validator\Constraints\ExpressionLanguageSyntax;
 use Symfony\Component\Validator\Constraints\ExpressionLanguageSyntaxValidator;
+use Symfony\Component\Validator\ConstraintValidatorInterface;
 use Symfony\Component\Validator\Test\ConstraintValidatorTestCase;
 
 /**
  * @group legacy
  */
 class ExpressionLanguageSyntaxValidatorTest extends ConstraintValidatorTestCase
 {
-    protected function createValidator(): ExpressionLanguageSyntaxValidator
+    protected function createValidator(): ConstraintValidatorInterface
     {
         return new ExpressionLanguageSyntaxValidator(new ExpressionLanguage());
     }