Update ollama.py (#12895)

duplicate option removed
**Description:**  An issue fix, http stop option duplicate removed.
**Issue:** the issue #12892 fix
**Dependencies:** no
**Tag maintainer:** @eyurtsev

---------

Co-authored-by: Erick Friis <erick@langchain.dev>

libs/langchain/langchain/llms/ollama.py

@@ -128,7 +128,8 @@ class _OllamaCommon(BaseLanguageModel):
             stop = self.stop
         elif stop is None:
             stop = []
-        params = {**self._default_params, "stop": stop, **kwargs}
+        params = {**self._default_params, **kwargs}
+        params["options"]["stop"] = stop
         response = requests.post(
             url=f"{self.base_url}/api/generate/",
             headers={"Content-Type": "application/json"},