qa_crowbarsetup: let crowbarpurge succeed
qa_crowbarsetup: let crowbarpurge succeed

with the recent restructuring, the exit code became relevant
but the killall returned an error
because it could not find the process to kill

vmoravec/automation,aspiers/automation,gosipyan/automation,gosipyan/automation,vmoravec/automation,aspiers/automation,SUSE-Cloud/automation,SUSE-Cloud/automation,SUSE-Cloud/automation,gosipyan/automation,vmoravec/automation,aspiers/automation,gosipyan/automation,SUSE-Cloud/automation,vmoravec/automation,aspiers/automation