Fix runIDPVM handling of comma-separated input list
Simple improvement to the runIDPVM.py script to handle comma-separated input lists. This allows using the script from a pathena --trf expression, where the %IN placeholder might resolve to such an input format.
Note that IDPVM is still usable through pathena through the InDetPhysValMonitoring_topOptions.py joboption but it is now deprecated, hence this MR.