INTPYTHON-869 - [LangChain] Update tests to use supported gpt model (langchain-ai#312)

Passing tests:
https://spruce.mongodb.com/version/696f91e258ffd000075e35e7/tasks?sorts=STATUS%3AASC%3BBASE_STATUS%3ADESC.

Author: NoahStapp

libs/langchain-mongodb/tests/integration_tests/test_agent_toolkit.py

@@ -55,9 +55,9 @@ def test_toolkit_response(db):
         CONNECTION_STRING, database=DB_NAME
     )
     if "AZURE_OPENAI_ENDPOINT" in os.environ:
-        llm = AzureChatOpenAI(model="gpt-4o-mini", timeout=60, seed=12345)
+        llm = AzureChatOpenAI(model="gpt-5-mini", timeout=60, seed=12345)
     else:
-        llm = ChatOpenAI(model="gpt-4o-mini", timeout=60, seed=12345)
+        llm = ChatOpenAI(model="gpt-5-mini", timeout=60, seed=12345)
 
     toolkit = MongoDBDatabaseToolkit(db=db_wrapper, llm=llm)
 

libs/langchain-mongodb/tests/utils.py

@@ -52,7 +52,7 @@ def create_llm() -> BaseChatModel:
     if os.environ.get("AZURE_OPENAI_ENDPOINT"):
         return AzureChatOpenAI(model="o4-mini", timeout=60, cache=False, seed=12345)
     if os.environ.get("OPENAI_API_KEY"):
-        return ChatOpenAI(model="gpt-4o-mini", timeout=60, cache=False, seed=12345)
+        return ChatOpenAI(model="gpt-5-mini", timeout=60, cache=False, seed=12345)
     return ChatOllama(model="llama3:8b", cache=False, seed=12345)