Update components/serializer.rst

Co-authored-by: Oskar Stark <[email protected]>

Author: ktherage

components/serializer.rst

@@ -1099,9 +1099,7 @@ always as a collection.
 
 .. note::
 
-    You may need to add some attributes on the root node. This can be done this way :
-
-    .. code-block:: php
+    You may need to add some attributes on the root node::
 
         $encoder = new XmlEncoder();
         $encoder->encode([
@@ -1110,16 +1108,11 @@ always as a collection.
             '#' => ['foo' => ['@bar' => 'value', '#' => 'baz']]
         ], 'xml');
 
-    This will generate the following XML :
-
-    .. code-block:: xml
-
-        <?xml version="1.0"?>
-        <response attribute1="foo" attribute2="bar">
-            <foo bar="value">
-               baz
-            </foo>
-        </response>
+        // will return:
+        // <?xml version="1.0"?>
+        // <response attribute1="foo" attribute2="bar">
+        // <foo bar="value">baz</foo>
+        // </response>
 
 .. tip::