temp fix for lumi report on workloadsummary

temp fix for #5216 
That is good catch, however, it doesn't seem to have duplicate records in vocms237 and we could make sure by
adding unique constraint here. https://github.com/dmwm/WMCore/blob/master/src/python/WMCore/WMBS/CreateWMBSBase.py#L107
However I am not sure not checking the condition would reduce the time greatly. maybe to half. We can check but still might not be enough.