Add FAQ for using model of preference on Cody CLI (#675)

<!-- Explain the changes introduced in your PR -->
This update introduces an answer to a question where users would like to
find out if they can use a model of choice to chat with Cody on CLI.

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Author: airamare01

docs/cody/faq.mdx

@@ -114,3 +114,13 @@ Yes, Cody supports the following cloud development environments:
 
 - vscode.dev and GitHub Codespaces (install from the VS Code extension marketplace)
 - Any editor supporting the [Open VSX Registry](https://open-vsx.org/extension/sourcegraph/cody-ai), including [Gitpod](https://www.gitpod.io/blog/boosting-developer-productivity-unleashing-the-power-of-sourcegraph-cody-in-gitpod), Coder, and `code-server` (install from the [Open VSX Registry](https://open-vsx.org/extension/sourcegraph/cody-ai))
+
+### Can I use my LLM of preference to chat with Cody on CLI?
+
+Yes you can. In the CLI you can use the following command to get started. Please replace `$name_of_the_model` with the LLM model of your choice.
+
+```
+cody chat --model '$name_of_the_model' -m 'Hi Cody!'
+```
+
+For example, to use Claude 3.5 Sonnet, you'd pass the following command in your terminal, `cody chat --model 'claude-3.5-sonnet' -m 'Hi Cody!'