Fix typo in kfp-basics/demo_lightweight notebook

[ca-scribner]

def my_sum_external_helper(a: float, b: float, c: float) -> float:
    """
    A function that sums its numeric arguments
    """
    return my_sum_helper(a, b, c)

# NOTE the extra argument here
my_sum_external_helper_component = func_to_container_op(my_sum_internal_helper,
                                                        base_image=BASE_IMAGE,
                                                        use_code_pickling=True,  # <----
                                                        )

should be

def my_sum_external_helper(a: float, b: float, c: float) -> float:
    """
    A function that sums its numeric arguments
    """
    return my_sum_helper(a, b, c)

# NOTE the extra argument here
my_sum_external_helper_component = func_to_container_op(my_sum_external_helper,
                                                        base_image=BASE_IMAGE,
                                                        use_code_pickling=True,  # <----
                                                        )

[ca-scribner]

While at it, can also add a note about python versions in the baseimage matching the one in the notebook. Maybe also add python -V reference, or change the BASE_IMAGE to just point to a notebook server image? Any way I can introspect the current notebook version?