DiscreteFunction should still be passed sys

Author: AayushSabharwal

src/systems/discrete_system/discrete_system.jl

@@ -224,7 +224,7 @@ function SciMLBase.DiscreteProblem(sys::DiscreteSystem, u0map = [], tspan = get_
     f_oop, _ = (@RuntimeGeneratedFunction(eval_module, ex) for ex in f_gen)
     f(u, p, iv) = f_oop(u, p, iv)
     fd = DiscreteFunction(f; syms = Symbol.(dvs), indepsym = Symbol(iv),
-                          paramsyms = Symbol.(ps))
+                          paramsyms = Symbol.(ps), sys = sys)
     DiscreteProblem(fd, u0, tspan, p; kwargs...)
 end