minor #14557 [Validator] Fix namespace of UserPassword and UserPasswordValidator (wkania)

This PR was merged into the 4.4 branch.

Discussion
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[Validator] Fix namespace of UserPassword and UserPasswordValidator

Commits
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4e0bdc5 [Validator] Fix namespace of UserPassword and UserPasswordValidator

Author: javiereguiluz

reference/constraints/UserPassword.rst

@@ -20,8 +20,8 @@ Applies to  :ref:`property or method <validation-property-target>`
 Options     - `groups`_
             - `message`_
             - `payload`_
-Class       :class:`Symfony\\Component\\Validator\\Constraints\\UserPassword`
-Validator   :class:`Symfony\\Component\\Validator\\Constraints\\UserPasswordValidator`
+Class       :class:`Symfony\\Component\\Security\\Core\\Validator\\Constraints\\UserPassword`
+Validator   :class:`Symfony\\Component\\Security\\Core\\Validator\\Constraints\\UserPasswordValidator`
 ==========  ===================================================================
 
 Basic Usage