Fixing deprecation and tests in 5.1

Author: weaverryan

tests/IntegrationTest.php

@@ -241,6 +241,9 @@ protected function configureContainer(ContainerBuilder $container, LoaderInterfa
     {
         $container->loadFromExtension('framework', [
             'secret' => 'foo',
+            'router' => [
+                'utf8' => true,
+            ],
             'assets' => [
                 'enabled' => $this->enableAssets,
             ],
@@ -297,9 +300,9 @@ public function renderFoo()
     }
 }
 
-if (method_exists(AbstractWebpackEncoreIntegrationTestKernel::class, 'configureRouting')) {
+if (Kernel::VERSION_ID >= 50100) {
     class WebpackEncoreIntegrationTestKernel extends AbstractWebpackEncoreIntegrationTestKernel {
-        protected function configureRouting(RoutingConfigurator $routes): void
+        protected function configureRoutes(RoutingConfigurator $routes): void
         {
             $routes->add('/foo', 'kernel:'.(parent::VERSION_ID >= 40100 ? ':' : '').'renderFoo');
         }