red teaming metrics are broken for conversation case

[sermakarevich]

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Describe the bug

there are two issues in one place:

        if isinstance(test_case, ConversationalTestCase):
            test_case = check_conversational_test_case_params(test_case, self)
        check_llm_test_case_params(test_case, required_params, self)

while

def check_conversational_test_case_params(
    test_case: ConversationalTestCase,
    test_case_params: List[LLMTestCaseParams],
    metric: BaseConversationalMetric,
    require_chatbot_role: bool = False,
):

1. check_conversational_test_case_params has 3 required params but passed 2
2. check_conversational_test_case_params does not return anything, so test_case is None-ified if it is a ConversationalTestCase

[penguine-ip]

@sermakarevich the red teaming metrics aren't meant to be used externally but if you make a PR happy to potentially incorperate it