scribusUnstable: fix build failure from poppler bump

Poppler was upgraded in [0] and therefore the build broke, as
poppler/goo/gtypes.h was moved into poppler/goo/gfile.h [1].

The patch is intended to be broght upstream and then can be reverted.

[0] https://github.com/NixOS/nixpkgs/commit/7757e43fcb15f3b3e21187787edaad54614ec7e6
[1] https://gitlab.freedesktop.org/poppler/poppler/commit/ef3ef702bc3dc845731e43215400448c5324efd4

pkgs/applications/office/scribus/poppler-0.73.0.patch

@@ -0,0 +1,12 @@
+diff --git a/scribus/plugins/import/pdf/slaoutput.h b/scribus/plugins/import/pdf/slaoutput.h
+--- a/scribus/plugins/import/pdf/slaoutput.h
++++ b/scribus/plugins/import/pdf/slaoutput.h
+@@ -28,7 +28,7 @@ for which a new license (GPL+exception) is in place.
+ #include "selection.h"
+ #include "vgradient.h"
+ 
+-#include <poppler/goo/gtypes.h>
++#include <poppler/goo/gfile.h>
+ #include <poppler/Object.h>
+ #include <poppler/OutputDev.h>
+ #include <poppler/Gfx.h>

pkgs/applications/office/scribus/unstable.nix

@@ -16,6 +16,8 @@ stdenv.mkDerivation rec {
     sha256 = "18xqhxjm8dl4w3izg7202i8vicfggkcvi0p9ii28k43b5ps1akg1";
   };
 
+  patches = [ ./poppler-0.73.0.patch ];
+
   enableParallelBuilding = true;
 
   buildInputs = [