Updates a fulfillment's properties.
To update a field's value, include the new value in the fulfillment field in the body params.
To remove a field's value, pass null.
The updateFulfillment() function returns a Promise that resolves when the fulfillment is updated.
Note: Updating line item IDs or fulfilled quantities is not allowed. To update line item IDs or quantities, delete the fulfillment and create it again.
You can only call this method when authenticated as a Wix app or Wix user identity.
Order and fulfillment IDs to be updated.
Available options to use when updating a fulfillment.