Fix #128906: Remove Docking Draw Callbacks After Deactivate

If we lose focus while splitting or docking we need to make sure that
the overlay drawing callbacks are stopped.

Pull Request: https://projects.blender.org/blender/blender/pulls/128957

source/blender/editors/screen/screen_ops.cc

@@ -4126,6 +4126,7 @@ static int area_join_modal(bContext *C, wmOperator *op, const wmEvent *event)
 {
   if (event->type == WINDEACTIVATE) {
     /* This operator can close windows, which can cause it to be re-run. */
+    area_join_exit(C, op);
     return OPERATOR_FINISHED;
   }