moka-icon-theme: add hook to symlink inherited icon themes

pkgs/data/icons/moka-icon-theme/default.nix

···
     sha256 = "015l02im4mha5z91dbchxf6xkp66d346bg3xskwg0rh3lglhjsrd";
   };
 
-  nativeBuildInputs = [ meson ninja gtk3 python3 faba-icon-theme ];
+  nativeBuildInputs = [
+    meson
+    ninja
+    gtk3
+    python3
+  ];
 
   propagatedBuildInputs = [
+    faba-icon-theme
     hicolor-icon-theme
   ];