rakefile: update ruby only extension check
rakefile: update ruby only extension check

rhosilver/rhodes-1,UIKit0/rhodes,UIKit0/rhodes,louisatome/rhodes,louisatome/rhodes,UIKit0/rhodes,rhosilver/rhodes-1,UIKit0/rhodes,louisatome/rhodes,UIKit0/rhodes,rhosilver/rhodes-1,UIKit0/rhodes,UIKit0/rhodes,UIKit0/rhodes,rhosilver/rhodes-1,rhosilver/rhodes-1,rhosilver/rhodes-1,UIKit0/rhodes,louisatome/rhodes,rhosilver/rhodes-1,rhosilver/rhodes-1,louisatome/rhodes,UIKit0/rhodes,rhosilver/rhodes-1,louisatome/rhodes,louisatome/rhodes,louisatome/rhodes,louisatome/rhodes,rhosilver/rhodes-1