minor #14738 Minor: Fix quotes (simon-watiau)

This PR was submitted for the 5.2 branch but it was merged into the 4.4 branch instead.

Discussion
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Minor: Fix quotes

style(serializer): Fix quotes

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Commits
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78de6f6 Minor: Fix quotes

Author: wouterj

components/serializer.rst

@@ -627,7 +627,7 @@ defines a ``Person`` entity with a ``firstName`` property:
 This custom mapping is used to convert property names when serializing and
 deserializing objects::
 
-    $serialized = $serializer->serialize(new Person("Kévin"), 'json');
+    $serialized = $serializer->serialize(new Person('Kévin'), 'json');
     // {"customer_name": "Kévin"}
 
 Serializing Boolean Attributes