Test `nix copy --substitute-on-destination` (cherry picked from commit ed93e51f4b0a8149521e3cf5b4f3ff4eabf5b060) Change-Id: I33f8b591f42acf96fd18f27758dd1141b4bbbb5f
I33f8b591f42acf96fd18f27758dd1141b4bbbb5f