minor #14283 Add missing ->end() method call (jdreesen)

This PR was merged into the 3.4 branch.

Discussion
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Add missing `->end()` method call

I think for the consistency it might be good to add an `->end()` call here.

Commits
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3ed2cf3 Add missing `->end()` method call

Author: javiereguiluz

components/config/definition.rst

@@ -752,7 +752,7 @@ By changing a string value into an associative array with ``name`` as the key::
                     ->then(function ($v) { return ['name' => $v]; })
                 ->end()
                 ->children()
-                    ->scalarNode('name')->isRequired()
+                    ->scalarNode('name')->isRequired()->end()
                     // ...
                 ->end()
             ->end()