[389-devel] Please review lib389 ticket 47584 (take #3): CI tests: add backup/restore of an instance

This review differs from previous with: * skip verbose option (use of log.level). * use glob.glob to retrieve files matching rather that os.walk * fix a bug in instanceBackupFS that did not return an already existing backup * add two functions to handle instance backup: clearInstanceBackupFS (to remove one or all backups of an instance), _infoInstanceBackupFS (just to keep path/pattern info of backup into a single routine) https://fedorahosted.org/389/attachment/ticket/47584/0003-Ticket-47584-CI...