Update items in a recurring sale

Example request

{
  "RecurringSaleId": "a6f8c4a3-3f25-4f73-b5c4-e8c1002bd8db",
  "discount": 1.5,
  "items": [
    {
      "ItemCatalog": "abc123",
      "Name": "item1",
      "Quantity": 1,
      "RivhitItemId": 0,
      "UnitPrice": 5
    },
    {
      "ItemCatalog": "abc124",
      "Name": "item2",
      "Quantity": 1,
      "RivhitItemId": 0,
      "UnitPrice": 5
    }
  ]
}