ipatests: ipa-migrate tool with -Z option (CACERTFILE)
    
    This patch add tests to check the scenarios associated with
    pagure tickets
    
    https://pagure.io/freeipa/issue/9642 - ipa-migrate - properly handle invalid certificates
    https://pagure.io/freeipa/issue/9619 - ipa-migrate starttls does not work
    
    Signed-off-by: Sudhir Menon <sumenon@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>