lesspipe: Fix build on OpenBSD

For some reason resholve can figure out that `file` built for
FreeBSD and Linux do not execute arguments, but not for OpenBSD.
Explicitly tell it that there is no problem

pkgs/by-name/le/lesspipe/package.nix

@@ -167,6 +167,7 @@ stdenv.mkDerivation rec {
       };
       execer = [
         "cannot:${iconv}/bin/iconv"
+        "cannot:${file}/bin/file"
       ];
     }}
     ${resholve.phraseSolution "lesscomplete" {
@@ -216,6 +217,9 @@ stdenv.mkDerivation rec {
         ];
         builtin = [ "setopt" ];
       };
+      execer = [
+        "cannot:${file}/bin/file"
+      ];
     }}
   '';