these 2 derivations will be built:
  /nix/store/dvqccvr5plfg3pz8ygqwhwwj0sgd61m3-nixos-test-driver-pg_repack.drv
  /nix/store/8i18a3rjvmqy0s6i28m8bhp61sg3nzfg-vm-test-run-pg_repack.drv