ci/eval/compare: Ignore null packages (#381262)

    pkg:

    if (lib.attrsets.hasAttrByPath pkg.path pkgs) then

      (

        if (builtins.tryEval (lib.attrsets.attrByPath pkg.path null pkgs)).success then

          true

        let

          value = lib.attrsets.attrByPath pkg.path null pkgs;

        in

        if (builtins.tryEval value).success then

          if value != null then true else builtins.trace "${pkg.name} exists but is null" false

        else

          builtins.trace "Failed to access ${pkg.name} even though it exists" false

      )