minor symfony#16870 [Console] Update questionhelper.rst (issamkhadiri1989)

This PR was submitted for the 6.0 branch but it was merged into the 4.4 branch instead.

Discussion
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[Console] Update questionhelper.rst

hello,

when running the example as it is, a deprecation message is shown (i'm on PHP 8.1.6). the deprecation message says that ``trim(): Passing null to parameter #1 ($string) of type string is deprecated``.
what if we add a normalizer that returns an empty string when the entered value is `null` otherwise returns the user's intial input.  with this suggestion, the example works great

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Commits
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bf9e245 Update questionhelper.rst

Author: javiereguiluz

components/console/helpers/questionhelper.rst

@@ -384,6 +384,9 @@ You can also use a validator with a hidden question::
         $helper = $this->getHelper('question');
 
         $question = new Question('Please enter your password');
+        $question->setNormalizer(function ($value) {
+            return null === $value ? '' : $value;
+        });
         $question->setValidator(function ($value) {
             if (trim($value) == '') {
                 throw new \Exception('The password cannot be empty');