trivial: contrib: Update README for proper docker command (Closes: #615)
trivial: contrib: Update README for proper docker command (Closes: #615)

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