minor #12453 [Serializer] Fixed some links to some classes (javiereguiluz)

This PR was merged into the 3.4 branch.

Discussion
----------

[Serializer] Fixed some links to some classes

Fixes #12437.

Commits
-------

c15e37c [SerializerFixed some links to some classes

Author: javiereguiluz

serializer/normalizers.rst

@@ -5,9 +5,9 @@ Normalizers
 ===========
 
 Normalizers turn **objects** into **arrays** and vice versa. They implement
-:class:`Symfony\\Component\\Serializer\\Normalizers\\NormalizerInterface` for
+:class:`Symfony\\Component\\Serializer\\Normalizer\\NormalizerInterface` for
 normalizing (object to array) and
-:class:`Symfony\\Component\\Serializer\\Normalizers\\DenormalizerInterface` for
+:class:`Symfony\\Component\\Serializer\\Normalizer\\DenormalizerInterface` for
 denormalizing (array to object).
 
 Normalizers are enabled in the serializer passing them as its first argument::