trivial: Do not cache junk if the LVFS returns 404
trivial: Do not cache junk if the LVFS returns 404

hughsie/fwupd,hughsie/fwupd,superm1/fwupd,superm1/fwupd,fwupd/fwupd,vathpela/fwupd,fwupd/fwupd,superm1/fwupd,vathpela/fwupd,vathpela/fwupd,fwupd/fwupd,hughsie/fwupd,vathpela/fwupd,hughsie/fwupd,fwupd/fwupd