[v9] fix: fix major compile time regression due to `concrete_getu`#3692

ChrisRackauckas merged 1 commit intoSciML:backport-v9SciML/ModelingToolkit.jl:backport-v9from

AayushSabharwal:as/concrete-getuAayushSabharwal/ModelingToolkit.jl:as/concrete-getuCopy head branch name to clipboard