intg: add Smartcard authentication tests
Two test for Smartcard authentication of a local user, i.e. a user
managed by the files provider, are added. One for a successful
authentication, the other for a failed authentication with a wrong PIN.
Related to https://pagure.io/SSSD/sssd/issue/3500
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>