Change language opt-out to language opt-in (#7823)

* Switch filtered_languages to chosen_languages

* Adjust interface

* Remove unused translations

app/controllers/settings/preferences_controller.rb

@@ -27,7 +27,7 @@ class Settings::PreferencesController < ApplicationController
   def user_params
     params.require(:user).permit(
       :locale,
-      filtered_languages: []
+      chosen_languages: []
     )
   end