Pagy I18n locale option is not validated before being used in a file path
Pagy::I18n.locale= did not validate its argument before using it as a path component to load the matching dictionary file (<locale>.yml). An application that assigns untrusted input to the locale — e.g. the common pattern Pagy::I18n.locale = params[:locale] — let that input influence which file Pagy attempted to load.