docs: fix formatting issue by adding missing code block fence in linux_nvidia.md (#33)

Signed-off-by: Rafael Zago <rafaelvzago@gmail.com>

Author: rafaelvzago

docs/getting-started/linux_nvidia.md

@@ -11,6 +11,7 @@ logo: images/ilab_dog.png
 !!! note
     These steps will pull down a premade `qna.yaml` so you can do a local build. Skip the `wget`, `mv`, and `ilab taxonomy diff` if you don't want to do this.
 
+```bash
 python3.11 -m venv --upgrade-deps venv
 source venv/bin/activate
 pip cache remove llama_cpp_python
@@ -141,4 +142,4 @@ you can save the completion script and source it from `~/.bashrc`:
 
 ```sh
 _ILAB_COMPLETE=fish_source ilab > ~/.config/fish/completions/ilab.fish
-```
+```