Removes labels from a contact.
If a label is no longer needed and you want to remove it from all contacts, you can delete it with Delete Label (in the Labels API).
Members are typically associated with a contact, each having a distinct member and contact ID. When passing the ID as a parameter, avoid presuming the IDs are identical since they represent separate entities.
You can only call this method when authenticated as a Wix app or Wix user identity.