fix docker-in-docker copying when not doing CONTINUE=1
fix docker-in-docker copying when not doing CONTINUE=1

jacen92/pi-gen,DigitaleGesellschaft/pi-gen,KingBrewer/pi-gen,timcoote/Pumpkin-gen,WLANThermo/pi-gen,BlokasLabs/modep,rkubes/pi-gen,BlokasLabs/modep,timcoote/Pumpkin-gen,timcoote/Pumpkin-gen,RPi-Distro/pi-gen