Fallback language for shy

incubator:Wt/shy is close to approval, once we can get (a) language verification and (b) the Phabricator is resolved. I have been asked by the community to set fr as the fallback language for shy. Please see incubator:User talk:StevenJ81/Archive 2#Tacawit wt as a independent project from the incubator ? (at the bottom of the section).