Martin Brennan 2965519c76
DEV: Add auto _map extensions for list site settings with no type (#23331)
Followup to eea74e0e32f704f0756202c3f3ae801bcc8ac8bb. Site settings
which are a list without a list_type should also have the _map
extension added which returns an array based on split("|").

For example:

```
SiteSetting.post_menu_map
=> ["read", "like"]
```
2023-08-30 16:14:06 +10:00
..
2023-06-08 16:12:13 -05:00
2023-06-13 22:02:21 +02:00