gns3-gui: Replace qt5Full with wrapQtApp (proper solution)

This will now properly wrap the gns3 binary using wrapQtApp instead of
unnecessarily adding qt5Full to the PATH (which significantly increases
the closure and often causes the build to break due to broken transitive
dependencies).
This supersedes the old approach from commit 0eaec4dee2.

pkgs/applications/networking/gns3/default.nix

@@ -1,4 +1,4 @@
-{ callPackage }:
+{ callPackage, libsForQt5 }:
 
 let
   stableVersion = "2.2.12";
@@ -24,7 +24,7 @@ let
         "0ykr61yiiizgvm3bzipa3l73rvj49wmrybbfwhvpgk3pscl5pa68")
     ];
   };
-  mkGui = args: callPackage (import ./gui.nix (addVersion args // extraArgs)) { };
+  mkGui = args: libsForQt5.callPackage (import ./gui.nix (addVersion args // extraArgs)) { };
   mkServer = args: callPackage (import ./server.nix (addVersion args // extraArgs)) { };
   guiSrcHash = "05nnil8ljyj6h366yrniv6syznhhbnb7nzjkz5785rb9pzjizs19";
   serverSrcHash = "0gmfdnymiw4w13qbcsvd71yj3hc9640n43c305vq39hahvsn7rvc";

pkgs/applications/networking/gns3/gui.nix

@@ -1,6 +1,6 @@
 { stable, branch, version, sha256Hash, mkOverride, commonOverrides }:
 
-{ lib, stdenv, python3, pkgs, fetchFromGitHub }:
+{ lib, python3, fetchFromGitHub, wrapQtAppsHook }:
 
 let
   defaultOverrides = commonOverrides ++ [
@@ -20,16 +20,20 @@ in python.pkgs.buildPythonPackage rec {
     sha256 = sha256Hash;
   };
 
+  nativeBuildInputs = [ wrapQtAppsHook ];
   propagatedBuildInputs = with python.pkgs; [
     sentry-sdk psutil jsonschema # tox for check
     # Runtime dependencies
     sip (pyqt5.override { withWebSockets = true; }) distro setuptools
-    pkgs.qt5Full
   ];
 
   doCheck = false; # Failing
+  dontWrapQtApps = true;
+  postFixup = ''
+      wrapQtApp "$out/bin/gns3"
+  '';
 
-  meta = with stdenv.lib; {
+  meta = with lib; {
     description = "Graphical Network Simulator 3 GUI (${branch} release)";
     longDescription = ''
       Graphical user interface for controlling the GNS3 network simulator. This