Fix bug found in DATREP-183
A bug was found in DATREP-183, the details of which can be found in the attachment of the ticket.
In short, the "startPars" passed to the "CaloExtension" function has the potential risk of being deleted twice. This MR tries to make a copy of startPars to avoid the problem.
Tag the relevant software experts: @goblirsc , @sroe , @goetz
Cheers,
Yichen