Update Menu Item unavailabilities

put https://partners.deliveroo.com/api/v1/brands/{brand_id}/menus/{id}/item_unavailabilities/{site_id}

Once a menu is sent to our platform, all the items in the menu are theoretically "available", therefore a customer can order them. This endpoint allows the caller to set items as "unavailable" or "hidden":

unavailable: every item ID marked as unavailable will be "greyed out", "striked-through" and marked as "sold out" on our platform until the end of the current day
hidden: every item ID marked as hidden will not be visible on the menu. The item will remain hidden from the menu until a subsequent update removes its hidden status.

The call acts as a complete override of all the item unavailabilities for the given menu/site; as a corollary, sending an empty array will make everything available again.

As mentioned above the call acts a complete override, see the following sequence of calls:

set orange_juice and granola unavailable
set orange_juice unavailable
as the result only orange_juice will remain unavailable.

This endpoint is rate limited at 1 request per minute per site.