minor #31900 [FrameworkBundle] Fixed replace argument of `routing.loa…

…der` service (yceruto)

This PR was merged into the 5.0-dev branch.

Discussion
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[FrameworkBundle] Fixed replace argument of `routing.loader` service

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

Fix #31702
> (1/1) OutOfBoundsException
The index "2" is not in the range [0, 1].

https://github.com/symfony/symfony/blob/bd8d8a2cfd50dffb4aa07908865931fb82a9e7bf/src/Symfony/Bundle/FrameworkBundle/Routing/DelegatingLoader.php#L33

Commits
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5e2e79d Fixed replace argument of `routing.loader` service

src/Symfony/Bundle/FrameworkBundle/DependencyInjection/FrameworkExtension.php

@@ -778,7 +778,7 @@ private function registerRouterConfiguration(array $config, ContainerBuilder $co
         $loader->load('routing.xml');
 
         if ($config['utf8']) {
-            $container->getDefinition('routing.loader')->replaceArgument(2, ['utf8' => true]);
+            $container->getDefinition('routing.loader')->replaceArgument(1, ['utf8' => true]);
         }
 
         $container->setParameter('router.resource', $config['resource']);