apparmor-utils: use libapparmor from python3Packages to fix overriding python version

pkgs/by-name/ap/apparmor-utils/package.nix

···
   buildPackages,
 
   # apparmor deps
-  libapparmor,
   apparmor-parser,
   apparmor-teardown,
 }:
+let
+  inherit (python3Packages) libapparmor;
+in
 python3Packages.buildPythonApplication {
   pname = "apparmor-utils";
   inherit (libapparmor) version src;