patch: remove usage of llm, chat model __call__ (#20788)

- `llm(prompt)` -> `llm.invoke(prompt)`
- `llm(prompt=prompt` -> `llm.invoke(prompt)` (same with `messages=`)
- `llm(prompt, callbacks=callbacks)` -> `llm.invoke(prompt,
config={"callbacks": callbacks})`
- `llm(prompt, **kwargs)` -> `llm.invoke(prompt, **kwargs)`

libs/community/langchain_community/llms/huggingface_endpoint.py

@@ -43,7 +43,7 @@ class HuggingFaceEndpoint(LLM):
                 repetition_penalty=1.03,
                 huggingfacehub_api_token="my-api-key"
             )
-            print(llm("What is Deep Learning?"))
+            print(llm.invoke("What is Deep Learning?"))
 
             # Streaming response example
             from langchain_core.callbacks.streaming_stdout import StreamingStdOutCallbackHandler
@@ -61,7 +61,7 @@ class HuggingFaceEndpoint(LLM):
                 streaming=True,
                 huggingfacehub_api_token="my-api-key"
             )
-            print(llm("What is Deep Learning?"))
+            print(llm.invoke("What is Deep Learning?"))
 
     """  # noqa: E501