a349629 ipa-custodia-checker now uses python3 shebang

Authored and Committed by cheimes a year ago
    ipa-custodia-checker now uses python3 shebang
    
    https://pagure.io/freeipa/issue/4985
    
    Signed-off-by: Christian Heimes <cheimes@redhat.com>
    Reviewed-By: Stanislav Laznicka <slaznick@redhat.com>