make sure an empty string translates to an empty SystematicSet
This would instead create a SystematicSet with an empty systematic variation...
This should address https://its.cern.ch/jira/browse/ATLASG-1519
GitLab jobs artifacts no longer stored forever as of Monday, November 4th 08:30h. Further information under https://cern.ch/otg0152576
This would instead create a SystematicSet with an empty systematic variation...
This should address https://its.cern.ch/jira/browse/ATLASG-1519