#2063: Update void* to std::byte* in HolderUser

src/vt/objgroup/holder/holder_user.h

@@ -61,7 +61,7 @@ struct HolderUser final : HolderObjBase<ObjT> {
 public:
   ObjT* get() override { return *obj_; }
   bool exists() override { return obj_ != nullptr; }
-  void* getPtr() override { return *obj_; }
+  std::byte* getPtr() override { return reinterpret_cast<std::byte*>(*obj_); }
 
   template <typename... Args>
   void reset(Args&&... args) {