Fix TanukiBot spec relying on outdated code

What does this MR do and why?

Fix pipeline https://jihulab.com/gitlab-cn/gitlab/-/pipelines/2660627/failures

Fix TanukiBot spec relying on outdated code

This addresses two problems that this spec had:

• It was relying on the FF ai_global_switch, but it should be ai_duo_chat_switch as of 716d18b2.
• The 'when no neighbors are found' example was passing because TanukiBot was disabled, not because of an empty response

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