fix workspace model list (#14033)

api/core/provider_manager.py

         )
 
         # append providers with langgenius/openai/openai
-        for provider_name in list(provider_name_to_provider_records_dict.keys()):
+        provider_name_list = list(provider_name_to_provider_records_dict.keys())
+        for provider_name in provider_name_list:
             provider_id = ModelProviderID(provider_name)
-            provider_name_to_provider_records_dict[str(provider_id)] = provider_name_to_provider_records_dict[
-                provider_name
-            ]
+            if str(provider_id) not in provider_name_list:
+                provider_name_to_provider_records_dict[str(provider_id)] = provider_name_to_provider_records_dict[
+                    provider_name
+                ]
 
         # Get all provider model records of the workspace
         provider_name_to_provider_model_records_dict = self._get_all_provider_models(tenant_id)