Change namespace

Co-authored-by: Alexandre Daubois <2144837+alexandre-daubois@users.noreply.github.com>

Author: cavasinf

validation/translations.rst

@@ -123,7 +123,7 @@ Now, create a ``validators`` catalog file in the ``translations/`` directory:
 You may need to clear your cache (even in the dev environment) after creating
 this file for the first time.
 
-You can also use :class:`Ns\\TranslatableMessage` to build your violation message::
+You can also use :class:`Symfony\\Component\\Translation\\TranslatableMessage` to build your violation message::
 
     use Symfony\Component\Translation\TranslatableMessage;
     use Symfony\Component\Validator\Constraints as Assert;