these 2 derivations will be built:
  /nix/store/x64q9z6qgvaygq9r2b9kp1x9qja70m1l-nixos-test-driver-pgmq.drv
  /nix/store/py4qq5v55i615cfywnhqdlijxsqmwx3k-vm-test-run-pgmq.drv