Broken links in Agents and tools documentation

[sergiopaniego]

In Agents and tools docs, there are some broken link in

Large Language Models (LLMs) trained to perform [causal language modeling](https://huggingface.co/docs/transformers/en/tasks/language_modeling.) can tackle a wide range of tasks

The final dot in https://huggingface.co/docs/transformers/en/tasks/language_modeling. is causing the issue.

Same in:

method which accepts a list of [messages](./chat_templating.)

, and

it follows the [messages format](./chat_templating.md)