removed CardLists for LLMs and ChatModels (#12307)

Problem statement: 
In the `integrations/llms` and `integrations/chat` pages, we have a
sidebar with ToC, and we also have a ToC at the end of the page.
The ToC at the end of the page is not necessary, and it is confusing
when we mix the index page styles; moreover, it requires manual work.
So, I removed ToC at the end of the page (it was discussed with and
approved by @baskaryan)

docs/scripts/model_feat_table.py

@@ -33,8 +33,6 @@
 
 # LLMs
 
-import DocCardList from "@theme/DocCardList";
-
 ## Features (natively supported)
 All LLMs implement the Runnable interface, which comes with default implementations of all methods, ie. `ainvoke`, `batch`, `abatch`, `stream`, `astream`. This gives all LLMs basic support for async, streaming and batch, which by default is implemented as below:
 - *Async* support defaults to calling the respective sync method in asyncio's default thread pool executor. This lets other async functions in your application make progress while the LLM is being executed, by moving this call to a background thread.
@@ -45,7 +43,6 @@
 
 {table}
 
-<DocCardList />
 """
 
 CHAT_MODEL_TEMPLATE = """\
@@ -56,8 +53,6 @@
 
 # Chat models
 
-import DocCardList from "@theme/DocCardList";
-
 ## Features (natively supported)
 All ChatModels implement the Runnable interface, which comes with default implementations of all methods, ie. `ainvoke`, `batch`, `abatch`, `stream`, `astream`. This gives all ChatModels basic support for async, streaming and batch, which by default is implemented as below:
 - *Async* support defaults to calling the respective sync method in asyncio's default thread pool executor. This lets other async functions in your application make progress while the ChatModel is being executed, by moving this call to a background thread.
@@ -69,7 +64,6 @@
 
 {table}
 
-<DocCardList />
 """