minor #10135 [Serializer] Fix typo (dlondero)

This PR was submitted for the master branch but it was merged into the 4.1 branch instead (closes #10135).

Discussion
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[Serializer] Fix typo

Looks like `unserialize` (which is not a method of the Serializer class) was used instead of `deserialize`.

Commits
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19fd8f7 Fix typo

Author: javiereguiluz

components/serializer.rst

@@ -1244,7 +1244,7 @@ This example shows how to serialize and deserialize those objects::
     $serialized = $serializer->serialize(new GitHubCodeRepository());
     // {"type": "github"}
 
-    $repository = $serializer->unserialize($serialized, CodeRepository::class, 'json');
+    $repository = $serializer->deserialize($serialized, CodeRepository::class, 'json');
     // instanceof GitHubCodeRepository
 
 If the class metadata factory is enabled as explained in the