these 2 derivations will be built:
  /nix/store/hfvn6jj00p8fxhmss0h33h4bdcm6bjma-nixos-test-driver-plpgsql_check.drv
  /nix/store/pg418xm94k1zb098jgc41d46bxlpjxml-vm-test-run-plpgsql_check.drv