unixtools.more: fix accessing version on darwin

pkgs/top-level/unixtools.nix

@@ -71,10 +71,17 @@ let
 
   # more is unavailable in darwin
   # so we just use less
-  more_compat = runCommand pkgs.less.name { } ''
-    mkdir -p $out/bin
-    ln -s ${pkgs.less}/bin/less $out/bin/more
-  '';
+  more_compat =
+    runCommand pkgs.less.name
+      {
+        passthru = {
+          inherit (pkgs.less) version;
+        };
+      }
+      ''
+        mkdir -p $out/bin
+        ln -s ${pkgs.less}/bin/less $out/bin/more
+      '';
 
   bins = mapAttrs singleBinary {
     # singular binaries