The flavour parameter is unused, so omit it (#317)

app/controllers/settings/flavours_controller.rb

@@ -16,7 +16,7 @@ class Settings::FlavoursController < Settings::BaseController
   end
 
   def update
-    user_settings.update(user_settings_params(params[:flavour]))
+    user_settings.update(user_settings_params)
     redirect_to action: 'show', flavour: params[:flavour]
   end
 
@@ -26,7 +26,7 @@ class Settings::FlavoursController < Settings::BaseController
     UserSettingsDecorator.new(current_user)
   end
 
-  def user_settings_params(flavour)
+  def user_settings_params
     { setting_flavour: params.require(:flavour),
       setting_skin: params.dig(:user, :setting_skin)
     }.with_indifferent_access