these 2 derivations will be built:
  /nix/store/m47lgr88wyspz3kir263i4j99w2n78za-nixos-test-driver-pgtap.drv
  /nix/store/a9lq2yy4viq9ln6r26cvn0lcijw3m4n6-vm-test-run-pgtap.drv