minor #20552 [Serializer] serializer[custom_normalizer]: fix reference to built-in normalizers (kaznovac)

This PR was merged into the 6.4 branch.

Discussion
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[Serializer] serializer[custom_normalizer]: fix reference to built-in normalizers

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fix reference on https://symfony.com/doc/6.4/serializer/custom_normalizer.html

Commits
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56c035a serializer[custom_normalizer]: fix reference to built-in normalizers

Author: javiereguiluz

serializer/custom_normalizer.rst

@@ -3,7 +3,7 @@ How to Create your Custom Normalizer
 
 The :doc:`Serializer component </serializer>` uses normalizers to transform
 any data into an array. The component provides several
-ref:`built-in normalizers <serializer-built-in-normalizers>` but you may
+:ref:`built-in normalizers <serializer-built-in-normalizers>` but you may
 need to create your own normalizer to transform an unsupported data
 structure.