unityhub: fix nix-env version parsing

pkgs/development/tools/unityhub/default.nix

@@ -1,15 +1,14 @@
 { lib, fetchurl, appimageTools, gsettings-desktop-schemas, gtk3 }:
 
-let
+appimageTools.wrapType2 rec {
+  pname = "unityhub";
   version = "2.3.2";
+
   src = fetchurl {
     # mirror of https://public-cdn.cloud.unity3d.com/hub/prod/UnityHub.AppImage
     url = "https://archive.org/download/unity-hub-${version}/UnityHub.AppImage";
     sha256 = "07nfyfp9apshqarc6pgshsczila6x4943hiyyizc55kp85aw0imn";
   };
-  name = "unityhub";
-in appimageTools.wrapType2 rec {
-  inherit name src;
 
   extraPkgs = (pkgs: with pkgs; with xorg; [ gtk2 gdk-pixbuf glib libGL libGLU nss nspr
     alsa-lib cups libcap fontconfig freetype pango
@@ -23,11 +22,11 @@ in appimageTools.wrapType2 rec {
   ]);
 
   extraInstallCommands =
-    let appimageContents = appimageTools.extractType2 { inherit name src; }; in
+    let appimageContents = appimageTools.extractType2 { inherit pname version src; }; in
     ''
       install -Dm444 ${appimageContents}/unityhub.desktop -t $out/share/applications
       substituteInPlace $out/share/applications/unityhub.desktop \
-        --replace 'Exec=AppRun' 'Exec=${name}'
+        --replace 'Exec=AppRun' 'Exec=${pname}'
       install -m 444 -D ${appimageContents}/unityhub.png \
         $out/share/icons/hicolor/64x64/apps/unityhub.png
     '';