* we also have to do this before we decide whether to accept early_data.
* In TLSv1.3 we've already negotiated our cipher so we do this call now.
* For < TLSv1.3 we defer it until after cipher negotiation.
* we also have to do this before we decide whether to accept early_data.
* In TLSv1.3 we've already negotiated our cipher so we do this call now.
* For < TLSv1.3 we defer it until after cipher negotiation.