minor #47472 Removed unused $event param of onKernelFinishRequest from RouterListener (githubfromgui)

This PR was merged into the 6.2 branch.

Discussion
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Removed unused $event param of onKernelFinishRequest from RouterListener

| Q             | A
| ------------- | ---
| Branch?       | 6.2
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| License       | MIT

The `$event` parameter in the `onKernelFinishRequest` for the `RouterListener` class seems to not be used. Other listeners such as `LocaleAwareListener`, `Firewall` and `FirewallListener` all takes advantage of this $event parameter.

`Symfony\Component\HttpKernel\EventListener\LocaleAwareListener`:
![image](https://user-images.githubusercontent.com/5428251/188231452-d5cd0772-0cc2-4e94-85d9-cea7f34edf95.png)

`Symfony\Component\Security\Http\Firewall`:
![image](https://user-images.githubusercontent.com/5428251/188230787-9e4a35cf-8c7f-45ab-93de-8d1d8a35bbc4.png)

`Symfony\Bundle\SecurityBundle\EventListener\FirewallListener`:
![image](https://user-images.githubusercontent.com/5428251/188231264-2d99f76e-f2f4-4c21-af37-196e3f21f788.png)

Plus, I could not find any Interface that ensures any contract over this method to all these classes above.

Commits
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3ff970677d Removed unused the $event parameter of onKernelFinishRequest from RouterListener.

Author: fabpot

EventListener/RouterListener.php

@@ -83,7 +83,7 @@ private function setCurrentRequest(?Request $request)
      * After a sub-request is done, we need to reset the routing context to the parent request so that the URL generator
      * operates on the correct context again.
      */
-    public function onKernelFinishRequest(FinishRequestEvent $event)
+    public function onKernelFinishRequest()
     {
         $this->setCurrentRequest($this->requestStack->getParentRequest());
     }