minor #30510 [Routing] removed a useless var (Jules Pietri)

This PR was merged into the 3.4 branch.

Discussion
----------

[Routing] removed a useless var

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | ~
| License       | MIT
| Doc PR        | ~

This was never documented, we should rely on `$routes->import()` instead.

Commits
-------

10c1313 [Routing] removed a useless var

src/Symfony/Component/Routing/Loader/PhpFileLoader.php

@@ -48,7 +48,7 @@ public function load($file, $type = null)
 
         if ($result instanceof \Closure) {
             $collection = new RouteCollection();
-            $result(new RoutingConfigurator($collection, $this, $path, $file), $this);
+            $result(new RoutingConfigurator($collection, $this, $path, $file));
         } else {
             $collection = $result;
         }