ipatests: update expected cksum for epn.conf
    
    The test test_epn.py::TestEPN::test_EPN_config_file ensures that
    /etc/ipa/epn.conf is installed and compares its checksum with an
    expected value.
    Commit fcad9c9 has changed the content of the file and the cksum
    must be updated to reflect the new content.
    
    Fixes: https://pagure.io/freeipa/issue/9419
    
    Signed-off-by: Florence Blanc-Renaud <flo@redhat.com>
    Reviewed-By: Anuja More <amore@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>