curl --request POST \
  --url https://api.nuwebgroup.com/v1/basket-items/update \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "itemId": 1,
  "basketId": 8,
  "quantity": 7
}
'

{
  "id": 5,
  "currencyId": 1,
  "currencySymbol": "£",
  "currencyCode": "GBP",
  "hasExpired": false,
  "expiresAt": "2021-01-13T11:03:55.000000Z",
  "expiresAtMilliseconds": 1610535835,
  "items": [],
  "orderItems": [],
  "count": 0,
  "totalExTax": 0,
  "discount": null,
  "tax": 0,
  "taxBreakdown": [],
  "total": 0,
  "totalDeferred": 0,
  "hasTaxes": false,
  "hasDiscounts": false,
  "hasDeferredPayments": false
}