test(classic): use typed model names in integration fixtures

Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>

libs/langchain/tests/integration_tests/chains/openai_functions/test_openapi.py

@@ -33,7 +33,7 @@ api_spec = {
 def test_openai_openapi_chain() -> None:
     from langchain_openai import ChatOpenAI
 
-    llm = ChatOpenAI(model="gpt-4o-mini", temperature=0)
+    llm = ChatOpenAI(model_name="gpt-4o-mini", temperature=0)
     chain = get_openapi_chain(json.dumps(api_spec), llm)
     output = chain.invoke({"query": "Fetch the top two posts."})
     assert len(output["response"]) == 2

libs/langchain/tests/integration_tests/retrievers/document_compressors/test_listwise_rerank.py

@@ -17,7 +17,7 @@ def test_list_rerank() -> None:
     ]
 
     reranker = LLMListwiseRerank.from_llm(
-        llm=ChatOpenAI(model="gpt-4.1-mini"),
+        llm=ChatOpenAI(model_name="gpt-4.1-mini"),
         top_n=3,
     )
     compressed_docs = reranker.compress_documents(documents, "Who is steve")