Update openai.py compatibility with azure 2023-07-01-preview (#7937)

Fixed missing "content" field in azure. 
Added a check for "content" in _dict (missing for azure
api=2023-07-01-preview)
@baskaryan

---------

Co-authored-by: Bagatur <[email protected]>

Author: pretidav

langchain/chat_models/openai.py

@@ -100,7 +100,9 @@ def _convert_dict_to_message(_dict: Mapping[str, Any]) -> BaseMessage:
     if role == "user":
         return HumanMessage(content=_dict["content"])
     elif role == "assistant":
-        content = _dict["content"] or ""  # OpenAI returns None for tool invocations
+        # Fix for azure
+        # Also OpenAI returns None for tool invocations
+        content = _dict.get("content", "")
         if _dict.get("function_call"):
             additional_kwargs = {"function_call": dict(_dict["function_call"])}
         else:

langchain/vectorstores/base.py

@@ -445,7 +445,7 @@ class VectorStoreRetriever(BaseRetriever):
     search_kwargs: dict = Field(default_factory=dict)
     allowed_search_types: ClassVar[Collection[str]] = (
         "similarity",
-        "similarity_score_threshold",
+        "similarityatscore_threshold",
         "mmr",
     )