fix: remove json_schema if response format is disabled. (#12014)

Signed-off-by: -LAN- <laipz8200@outlook.com>

api/core/model_runtime/model_providers/openai/llm/llm.py

@@ -421,7 +421,11 @@ class OpenAILargeLanguageModel(_CommonOpenAI, LargeLanguageModel):
 
         # text completion model
         response = client.completions.create(
-            prompt=prompt_messages[0].content, model=model, stream=stream, **model_parameters, **extra_model_kwargs
+            prompt=prompt_messages[0].content,
+            model=model,
+            stream=stream,
+            **model_parameters,
+            **extra_model_kwargs,
         )
 
         if stream:
@@ -593,6 +597,8 @@ class OpenAILargeLanguageModel(_CommonOpenAI, LargeLanguageModel):
                 model_parameters["response_format"] = {"type": "json_schema", "json_schema": schema}
             else:
                 model_parameters["response_format"] = {"type": response_format}
+        elif "json_schema" in model_parameters:
+            del model_parameters["json_schema"]
 
         extra_model_kwargs = {}