minor #16142 [Serializer] Remove duplicate colon (sebpacz)

This PR was merged into the 4.4 branch.

Discussion
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[Serializer] Remove duplicate colon

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Commits
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d2ebd70 [Serializer] Remove colon

Author: javiereguiluz

components/serializer.rst

@@ -694,7 +694,7 @@ Normalizers
 -----------
 
 Normalizers turn **object** into **array** and vice versa. They implement
-::class:`Symfony\\Component\\Serializer\\Normalizer\\NormalizableInterface`
+:class:`Symfony\\Component\\Serializer\\Normalizer\\NormalizableInterface`
 for normalize (object to array) and
 :class:`Symfony\\Component\\Serializer\\Normalizer\\DenormalizableInterface` for denormalize
 (array to object).