these 2 derivations will be built:
  /nix/store/cqprv006m3jwalw17k01d3rjw7d84y9d-nixos-test-driver-pg_repack.drv
  /nix/store/vknyj5qyap5gsby45fr3226kjdjbqvp0-vm-test-run-pg_repack.drv