these 2 derivations will be built:
  /nix/store/i5hpi55aajiafbad7fj3gp8yaj3d1j45-nixos-test-driver-pg_cron.drv
  /nix/store/kx4d303hzq0z9dcw719s0llq40xwd3j0-vm-test-run-pg_cron.drv