libgourou: Update homepage URL

pkgs/by-name/li/libgourou/package.nix

···
 
   meta = with lib; {
     description = "Implementation of Adobe's ADEPT protocol for ePub/PDF DRM";
-    homepage = "https://indefero.soutade.fr/p/libgourou";
+    homepage = "https://forge.soutade.fr/soutade/libgourou";
     license = licenses.lgpl3Plus;
     maintainers = with maintainers; [ autumnal ];
     platforms = platforms.all;