dpkg: Call standard_shutdown after invoking the post hooks

The error unwinding is part of the shutdown, and the invoke hooks
machinery might call ohshit, so it should be done at the end when
there's no more error handling in place.

src/main.c

@@ -721,10 +721,10 @@ int main(int argc, const char *const *argv) {
 
   actionfunction(argv);
 
-  standard_shutdown();
-
   if (is_invoke_action(cipaction->arg))
     run_invoke_hooks(cipaction->olong, post_invoke_hooks);
 
+  standard_shutdown();
+
   return reportbroken_retexitstatus();
 }