replicainstall: better client install exception handling
    
    The exception handling of client install inside replica installation
    was rather promiscuous, hungrily eating any possible exception thrown
    at it. Scoped down the try-except block and reduced its promiscuity.
    This change should improve the future development experience debugging
    this part of the code.
    
    https://pagure.io/freeipa/issue/6183
    
    Reviewed-By: Tomas Krizek <tkrizek@redhat.com>
    Reviewed-By: Jan Cholasta <jcholast@redhat.com>