[Validator] fixed deprecation notices for BuildViolation() calls in constraints

Author: fabpot

Core/Validator/Constraints/UserPasswordValidator.php

@@ -14,6 +14,7 @@
 use Symfony\Component\Security\Core\User\UserInterface;
 use Symfony\Component\Security\Core\Encoder\EncoderFactoryInterface;
 use Symfony\Component\Security\Core\Authentication\Token\Storage\TokenStorageInterface;
+use Symfony\Component\Validator\Context\ExecutionContextInterface;
 use Symfony\Component\Validator\Constraint;
 use Symfony\Component\Validator\ConstraintValidator;
 use Symfony\Component\Validator\Exception\ConstraintDefinitionException;