these 2 derivations will be built:
  /nix/store/kwd3njjgr3dffn9rnp0i354wf2r6lp4q-nixos-test-driver-postgis.drv
  /nix/store/7qxx26z6g12rkn967lydhb0c9id94khx-vm-test-run-postgis.drv