minor #13904 Fix wrong RoutingConfigurator#import usage (BafS)

This PR was merged into the 5.1 branch.

Discussion
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Fix wrong RoutingConfigurator#import usage

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Commits
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f20f59b Fix wrong RoutingConfigurator#import usage

Author: javiereguiluz

configuration/micro_kernel_trait.rst

@@ -174,12 +174,12 @@ hold the kernel. Now it looks like this::
         {
             // import the WebProfilerRoutes, only if the bundle is enabled
             if (isset($this->bundles['WebProfilerBundle'])) {
-                $routes->import('@WebProfilerBundle/Resources/config/routing/wdt.xml', '/_wdt');
-                $routes->import('@WebProfilerBundle/Resources/config/routing/profiler.xml', '/_profiler');
+                $routes->import('@WebProfilerBundle/Resources/config/routing/wdt.xml')->prefix('/_wdt');
+                $routes->import('@WebProfilerBundle/Resources/config/routing/profiler.xml')->prefix('/_profiler');
             }
 
             // load the annotation routes
-            $routes->import(__DIR__.'/../src/Controller/', '/', 'annotation');
+            $routes->import(__DIR__.'/../src/Controller/', 'annotation');
         }
 
         // optional, to use the standard Symfony cache directory