these 2 derivations will be built:
  /nix/store/fbj7mdg85z8wh7gm4ixa454zhsa5jg6q-nixos-test-driver-pg_jsonschema.drv
  /nix/store/qasxkmfi55vm9ymjhprx0sl27jn9sm9y-vm-test-run-pg_jsonschema.drv