Fix ROOT-8096
Fix ROOT-8096

Add proper support for template parameter pack in
cling::ForwardDeclPrinter::VisitTemplateArgument

karies/cling,marsupial/cling,karies/cling,karies/cling,karies/cling,karies/cling,marsupial/cling,root-mirror/cling,karies/cling,marsupial/cling,marsupial/cling,root-mirror/cling,root-mirror/cling,marsupial/cling,root-mirror/cling,marsupial/cling,root-mirror/cling,root-mirror/cling