Use .js_root instead place of hash accessor

Author: jhirn

lib/generators/stimulus/stimulus_generator.rb

@@ -11,7 +11,7 @@ class StimulusGenerator < Rails::Generators::NamedBase # :nodoc:
 
   def copy_view_files
     @attribute = stimulus_attribute_value(controller_name)
-    template "controller.js", "#{options[:js_root]}/controllers/#{controller_name}_controller.js"
+    template "controller.js", "#{options.js_root}/controllers/#{controller_name}_controller.js"
     rails_command "stimulus:manifest:update" unless Rails.root.join("config/importmap.rb").exist? || options[:skip_manifest]
   end