Motivation for this change

Gave runtime error before

Note that while it runs with this change, it throws a warning at runtime because the variable drvPath isn't defined in this line: https://github.com/NixOS/nixpkgs/blob/master/maintainers/scripts/nixpkgs-lint.pl#L151. My perl is insufficient to decipher the meaning of this line and how to get rid of the warning.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option build-use-sandbox in nix.conf on non-NixOS)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.