Revert "tchu-refactor-chat-bot-enabled-checks"

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Revert "Merge branch 'tchu-refactor-chat-bot-enabled-checks' into 'master'"

This reverts merge request !118968 (merged)

We've discovered an issue with the GitLab.com check that prevents feature launch. This MR reverts it

In that MR we've replaced user&.has_paid_namespace?(plans: [::Plan::ULTIMATE]) with user.has_paid_namespace?(plans: [::EE::User::AI_SUPPORTED_PLANS]), which results in [["gold", "ultimate", "ultimate_trial", "opensource"]]. It means that this check always returns false

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