fix: Support shared model

--bug=1061852 --user=张展玮 【应用】自动生成提示词时，如果使用的是共享模型，生成失败，提示模型不存在或不是大语言模型 https://www.tapd.cn/62980211/s/1774010

Author: zhanweizhang7

apps/chat/serializers/chat.py

@@ -168,7 +168,7 @@ def generate_prompt(self, instance: dict, with_valid=True):
         q = prompt.replace("{userInput}", message)
         messages[-1]['content'] = q
 
-        model_exist = QuerySet(Model).filter(workspace_id=workspace_id,
+        model_exist = QuerySet(Model).filter(
                                              id=model_id,
                                              model_type = "LLM"
                                              ).exists()