Generated tests don't handle tests without values

[stefanvanburen]

https://github.com/cloud-custodian/cel-python/blob/bc7504741dbedf93f869f3024d9fbe431a37cf04/features/math_ext.textproto#L29-L36

I believe these tests are meant to check if the return value is True, but when run:

$ uv run behave -i math_ext -n greatest_int_result/binary_with_decimal
@conformance
Feature: math_ext # features/math_ext.feature:2
  Tests for the math extension library.
  @wip
  Scenario: greatest_int_result/binary_with_decimal               # features/math_ext.feature:27
    When CEL expression 'math.greatest(1, 1.0) == 1' is evaluated # features/steps/integration_binding.py:400 0.067s
    Then none is None                                             # None

The Then none is None doesn't seem right. cc @hudlow