ipatests: set default 389-ds log level to 0
    
    During integration tests, the log level of 8192 (replication debugging)
    was excessive and made reading 389-ds logs very hard without providing
    any useful information.
    
    Part of: https://pagure.io/freeipa/issue/7162
    Signed-off-by: Tomas Krizek <tkrizek@redhat.com>
    Reviewed-By: Thierry Bordaz <tbordaz@redhat.com>
    Reviewed-By: Rob Crittenden <rcritten@redhat.com>