addRecipientsAsync 
suspend fun addRecipientsAsync(recipients: Array<RecipientWithRights>): Map<String, ActionStatus>
Add new recipients to this session. These recipients will be able to read all encrypted messages of this session.
Return 
A Map<String, ActionStatus> instance.
Parameters 
| recipients | The Seald IDs with the associated rights of users to add to this session. | 
Throws 
| SealdException |