Test fixing

Author: ChrisRackauckas

src/solve.jl

@@ -1304,7 +1304,7 @@ end
 hasdualpromote(u0, t) = true
 
 function promote_f(f::SplitFunction, ::Val{specialize}, u0, p, t) where {specialize}
-    typeof(f.cache) === typeof(u0) && isinplace(f) ? f : remake(f, cache = zero(u0))
+    typeof(f._func_cache) === typeof(u0) && isinplace(f) ? f : remake(f, _func_cache = zero(u0))
 end
 prepare_alg(alg, u0, p, f) = alg