Incorrect PropertyReference

[Sveino]

The namespace for the PropertyReference must change from http://iec.ch/TC57/CIM100#PropertyReference to http://entsoe.eu/ns/nc#PropertyReference

[Haigutus]

Fix needed for the type -> https://energy.referencedata.eu/PropertyReference/

[Haigutus]

@gridDigIt assigning to you, please correct the source file -> https://github.com/Haigutus/Energy-Reference-Data/blob/master/GeneratedData/PropertyReference.rdf

[griddigit-ci]

This issue was fixed with the last comit. Kristjan, can you verify and then close the issue?