these 2 derivations will be built:
  /nix/store/6szqri9dwqjfz0gfyjx0iddw54245c58-nixos-test-driver-pg_net.drv
  /nix/store/kx2v6g6y4gxahvxxgv6fps61jmwq3xgc-vm-test-run-pg_net.drv