fix: add getproperty method for backwards compatibility

Author: AayushSabharwal

src/scimlfunctions.jl

@@ -4597,3 +4597,14 @@ function SymbolicIndexingInterface.observed(fn::AbstractSciMLFunction, sym::Symb
 end
 
 SymbolicIndexingInterface.constant_structure(::AbstractSciMLFunction) = true
+
+function Base.getproperty(x::Union{ODEFunction, SplitFunction, DAEFunction}, sym::Symbol)
+  if sym == :initializeprob || sym == :update_initializeprob! || sym == :initializeprobmap || sym == :initializeprobpmap
+    if x.initialization_data === nothing
+      return nothing
+    else
+      return getproperty(x.initialization_data, sym)
+    end
+  end
+  return getfield(x, sym)
+end