minor #14415 [OptionsResolver] Add Info() method sample (yceruto)

This PR was merged into the 5.1 branch.

Discussion
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[OptionsResolver] Add Info() method sample

Fix: #13090

Commits
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0605be9 Add info() method sample

Author: javiereguiluz

components/options_resolver.rst

@@ -811,7 +811,9 @@ method::
             $resolver->define('host')
                 ->required()
                 ->default('smtp.example.org')
-                ->allowedTypes('string');
+                ->allowedTypes('string')
+                ->info('The IP address or hostname');
+
             $resolver->define('transport')
                 ->required()
                 ->default('transport')