Method clone_shared_ptr

tests/test_class_sh_mi_thunks.cpp:131–133

        return new Tiger(*this); // upcast
    }
    std::shared_ptr<Animal> clone_shared_ptr() const override {
        return std::make_shared<Tiger>(*this); // upcast
    }
    std::unique_ptr<Animal> clone_unique_ptr() const override {
        return std::unique_ptr<Tiger>(new Tiger(*this)); // upcast
    }