Add chat api to Mistral API

Summary: Added Chat API implementation to Mistral API

Reviewed By: csahana95

Differential Revision: D59539597

fbshipit-source-id: 2b6614be80c24023d067f6a19d843c5d88e81f08

CybersecurityBenchmarks/benchmark/llm.py

@@ -78,13 +78,15 @@ def chat(
     @abstractmethod
     def chat_with_system_prompt(
         self,
+        system_prompt: str,
         prompt_with_history: List[str],
         guided_decode_json_schema: Optional[str] = None,
     ) -> str:
         """
         Abstract method to chat with an LLM with given prompts as well as system prompt and return the response.
 
         Args:
+            system_prompt (str): The system prompt to send to the LLM.
             prompt_with_history ([str]): The prompt to send to the LLM along with chat history. The last string in the list is the prompt.
 
         Returns: