partners: fix of issue #24880 (#25229)

- Description: As described in the related issue: There is an error
occuring when using langchain-openai>=0.1.17 which can be attributed to
the following PR: #23691
Here, the parameter logprobs is added to requests per default.
However, AzureOpenAI takes issue with this parameter as stated here:
https://learn.microsoft.com/en-us/azure/ai-services/openai/how-to/chatgpt?tabs=python-new&pivots=programming-language-chat-completions
-> "If you set any of these parameters, you get an error."
Therefore, this PR changes the default value of logprobs parameter to
None instead of False. This results in it being filtered before the
request is sent.
- Issue: #24880
- Dependencies: /

Co-authored-by: blaufink <sebastian.brueckner@outlook.de>

libs/partners/openai/langchain_openai/chat_models/base.py

@@ -332,7 +332,7 @@ class BaseChatOpenAI(BaseChatModel):
     """Penalizes repeated tokens according to frequency."""
     seed: Optional[int] = None
     """Seed for generation"""
-    logprobs: Optional[bool] = False
+    logprobs: Optional[bool] = None
     """Whether to return logprobs."""
     top_logprobs: Optional[int] = None
     """Number of most likely tokens to return at each token position, each with