## Description
Add listmonk mailing list subscribe and unsubscribe
## Tests
Tested getSubscriberID, unsubscribe, and subscribe using a locally
running listmonk server with different parameters.
- [x] A new subscriber is created and added to the listmonk campaign
mailing list on listmonkSubscribe() for the given list IDs
- [x] Subscriber is removed from listmonk campaign mailing list on
listmonkUnsubscribe() for the given list IDs
- [x] The old email address is unsubscribed, and the new email is
subscribed when a user updates the email