gtk-sharp: wrap output executables

Fixes the below build error in gnome-sharp which appeared after #52712

/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/bin/gapi2-fixup --api=art-api.xml --metadata=./Art.metadata  --symbols=./art-symbols.xml
rm -f generated/* &&    \
/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/bin/gapi2-codegen --generate art-api.xml \
-I:/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/lib/pkgconfig/../../share/gapi-2.0/pango-api.xml -I:/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/lib/pkgconfig/../../share/gapi-2.0/atk-api.xml -I:/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/lib/pkgconfig/../../share/gapi-2.0/gdk-api.xml -I:/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/lib/pkgconfig/../../share/gapi-2.0/gtk-api.xml -I:/nix/store/wsqld4bccm0bwjnn1gj9cr32qscz4qk7-gtk-sharp-2.12.10/lib/pkgconfig/../../share/gapi-2.0/glib-api.xml      \
--outdir=generated --customdir=. --assembly-name=art-sharp      \
--gluelib-name=artsharpglue-2 --glue-filename=glue/generated.c          \
--glue-includes=                                                \
&& touch generated-stamp

Unhandled Exception:
System.MissingMethodException: Method 'string.Split' not found.
  at GtkSharp.Generation.SimpleGen..ctor (System.String ctype, System.String type, System.String default_value) [0x00000] in <d117698e7b8a4f9b867143c99aa161ba>:0
  at GtkSharp.Generation.SymbolTable..ctor () [0x00011] in <d117698e7b8a4f9b867143c99aa161ba>:0
  at GtkSharp.Generation.SymbolTable.get_Table () [0x0000a] in <d117698e7b8a4f9b867143c99aa161ba>:0
  at GtkSharp.Generation.CodeGenerator.Main (System.String[] args) [0x0003e] in <d117698e7b8a4f9b867143c99aa161ba>:0
[ERROR] FATAL UNHANDLED EXCEPTION: System.MissingMethodException: Method 'string.Split' not found.
  at GtkSharp.Generation.SimpleGen..ctor (System.String ctype, System.String type, System.String default_value) [0x00000] in <d117698e7b8a4f9b867143c99aa161ba>:0