PyUtils: Update diff-root to work with xAOD::EventAuxInfo_v3
No one complained about this just yet but I see ART tests where we compare ESD files are complaining about not being able to read event information, which is needed if the user asks for reordering events. In upstream data formats, such as ESD, the type name, including the class version number, is part of the branch name. After !48676 (merged) we move to a newer version of xAOD::EventAuxInfo and diff-root should be updated accordingly.