minor #13953 Add missing path in PHP routing configuration example (ocrampete16)

This PR was merged into the 4.4 branch.

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Add missing path in PHP routing configuration example

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The annotations and XML examples both specify `/contact` as the path to use.

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8cab7bb Add missing path in PHP routing configuration example

Author: javiereguiluz

routing.rst

@@ -302,7 +302,7 @@ arbitrary matching logic:
         use Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator;
 
         return function (RoutingConfigurator $routes) {
-            $routes->add('contact', '')
+            $routes->add('contact', '/contact')
                 ->controller([DefaultController::class, 'contact'])
                 ->condition('context.getMethod() in ["GET", "HEAD"] and request.headers.get("User-Agent") matches "/firefox/i"')
                 // expressions can also include config parameters: