Anyone who worked as hard for her money – and for a professional respect that came too late – as Donna Summer did deserves so much more than this. A jukebox musical that could undo all the genre rehab delivered by superior shows built around Carole King and, if you want to stretch the definition a bit to include Lazarus, David Bowie, Broadway’s Summer: The Donna Summer Musical, opening tonight, is as unimaginative as its title. With the saving graces of really fine vocal…