webui: notify psw change success only once
    
    Password change initiated from header menu notified success twice.
    First one in `dialogs.password.dialog` and second one in a success
    callback. The second notification was removed.
    
    Caused by:
    https://fedorahosted.org/freeipa/changeset/870db2f677dff01750aeec104c90fce3ca0e54be/
    
    Reviewed-By: Endi Sukma Dewata <edewata@redhat.com>