sparse_set: minor changes

src/entt/entity/sparse_set.hpp

@@ -77,7 +77,7 @@ struct sparse_set_iterator final {
     }
 
     [[nodiscard]] constexpr pointer operator->() const noexcept {
-        return packed->data() + index();
+        return std::addressof(operator[](0));
     }
 
     [[nodiscard]] constexpr reference operator*() const noexcept {