minor #19725 [HttpKernel] MapQueryParameter regex example correction (lkolndeep)

This PR was merged into the 6.4 branch.

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[HttpKernel] MapQueryParameter regex example correction

Correction of the example using MapQueryParameter with the filter using a regex.

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54bb5cb MapQueryParameter regex example correction

Author: javiereguiluz

controller.rst

@@ -375,7 +375,7 @@ attribute, arguments of your controller's action can be automatically fulfilled:
     // ...
 
     public function dashboard(
-        #[MapQueryParameter(filter: \FILTER_VALIDATE_REGEXP, options: ['regexp' => '/^\w++$/'])] string $firstName,
+        #[MapQueryParameter(filter: \FILTER_VALIDATE_REGEXP, options: ['regexp' => '/^\w+$/'])] string $firstName,
         #[MapQueryParameter] string $lastName,
         #[MapQueryParameter(filter: \FILTER_VALIDATE_INT)] int $age,
     ): Response