Fix tests

Author: skryukov

lib/generators/inertia/install/install_generator.rb

@@ -164,7 +164,7 @@ def install_example_page
 
         say 'Adding a route for the example Inertia controller'
         route "get 'inertia-example', to: 'inertia_example#index'"
-        unless File.read('config/routes.rb').match?(/^\s*root\s+/)
+        unless File.read(file_path('config/routes.rb')).match?(/^\s*root\s+/)
           route "root 'inertia_example#index'"
         end