guardian setup allows more guardians than specified

[otech47]

When the leader enters the number of guardians (ex: 4), when reaching the invite members step, more than 4 followers are allowed to participate in the verification process. Not sure if this is expected behavior but we were able to proceed with the ceremony with 5 guardians anyway... unsure if this has unexpected side effects

[Kodylow]

Needs to get fixed as part of #482 , this is a backend issue where the setup leader should stop accepting connections once it gets to the total guardians set in the previous SetConfiguration step @dpc < for tracking