Fix: Use request body in curl log for Gemini streaming mode (#9736)

Author: fengjiajie

litellm/llms/vertex_ai/gemini/vertex_and_google_ai_studio_gemini.py

@@ -1029,7 +1029,7 @@ async def async_streaming(
             input=messages,
             api_key="",
             additional_args={
-                "complete_input_dict": data,
+                "complete_input_dict": request_body,
                 "api_base": api_base,
                 "headers": headers,
             },