Merge pull request #17777 from bruvzg/macos_exit_code

[macOS] Return exit code specified by `OS.exit_code` parameter.

platform/osx/godot_main_osx.mm

@@ -101,5 +101,5 @@ int main(int argc, char **argv) {
 
 	Main::cleanup();
 
-	return 0;
+	return os.get_exit_code();
 };