Add wait_still_screen to menu_launch_type.

This is actually a very useful to wait a little bit before
we try to operate with the started application, especially
if we want to send keys.

Having this wait time here can save us doing this every time,
we start an application.

lib/utils.pm

@@ -1363,6 +1363,7 @@ sub menu_launch_type {
     # Wait for KDE to place focus correctly.
     wait_still_screen 2;
     send_key 'ret';
+    wait_still_screen 3;
 }
 
 sub tell_source {