The default List-Unsubscribe header link needs to be edited

The List-Unsubscribe header is a standard header that allows email recipients to easily unsubscribe from a mailing list. This header can contain one or more URLs or email addresses that the recipient's email client can use to automatically unsubscribe them. Some email clients (like Gmail) display an "Unsubscribe" button based on this header.

Here’s an example of how you might use the List-Unsubscribe header in an email:
List-Unsubscribe: <mailto:unsubscribe@example.com>, <http://example.com/unsubscribe>

The question is how can we add the link to the external system in Responsys?
Where do we configure this link?