minor #21180 [Serializer] Fix classname comment in Create a Custom Encoders section (Fuzip)

This PR was merged into the 7.3 branch.

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[Serializer] Fix classname comment in Create a Custom Encoders section

Fix classname comment in `Creating a Custom Encoder` section

Commits
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09bb042 Update encoders.rst

Author: javiereguiluz

serializer/encoders.rst

@@ -271,7 +271,7 @@ Creating a Custom Encoder
 Imagine you want to serialize and deserialize `NEON`_. For that you'll have to
 create your own encoder::
 
-    // src/Serializer/YamlEncoder.php
+    // src/Serializer/NeonEncoder.php
     namespace App\Serializer;
 
     use Nette\Neon\Neon;