these 2 derivations will be built:
  /nix/store/k6j4xfssqgqad0nc79n05wlagnn2sv4j-nixos-test-driver-pg_repack.drv
  /nix/store/fba35amkmwhsqds5z6x1ixbbz14jkdsm-vm-test-run-pg_repack.drv