Fix 109320: Crash when showing tooltip in menu search (Intel MacOS)

`uiBut` cannot simply be zero-allocated any more and needs proper construction
(so the `std::function` members can be constructed properly for example). I'm
not entirely sure where and how exactly the crash happens (happens in release
builds only, so probably optimization related), but this change must be done
either way and fixes the issue.

source/blender/editors/interface/interface_template_search_menu.cc

@@ -436,7 +436,7 @@ static MenuSearch_Data *menu_items_from_ui_create(
   const uiStyle *style = UI_style_get_dpi();
 
   /* Convert into non-ui structure. */
-  MenuSearch_Data *data = (MenuSearch_Data *)MEM_callocN(sizeof(*data), __func__);
+  MenuSearch_Data *data = MEM_new<MenuSearch_Data>(__func__);
 
   DynStr *dyn_str = BLI_dynstr_new_memarena();