[Security] Renamed catalonian translation file

Renamed as validators file in [Validator](https://github.com/symfony/symfony/blob/master/src/Symfony/Component/Validator/Resources/translations/validators.ca.xlf) and in [Form](https://github.com/symfony/symfony/blob/master/src/Symfony/Component/Form/Resources/translations/validators.ca.xlf) following ISO639-1 language code.