Broken / outdated link to Julia Style Guide (docs/style-guides/julia/README.md)

### Description

The link to the Julia style guide appears to be broken or outdated.

Specifically, the path:

stdlib/docs/style-guides/julia/README.md

does not resolve to a valid file anymore. The page references a "Julia Style Guide" with a TODO, but the link itself is not accessible.

The link does not work and results in a missing file / dead reference

It’s unclear whether the Julia style guide was intentionally removed or never finalized.

Happy to help with a fix or PR if guidance is provided.

Start by inspecting the reference to the Julia Style Guide in stdlib/docs/style-guides/julia/README.md and confirm whether the target file exists. Determine from the surrounding documentation whether the guide should be updated or the dead reference removed, then verify that the resulting link or page no longer points to a missing file.

Rédigé par le modèle d'indexation à partir du texte de l'issue.