Bump devalue from 5.6.3 to 5.8.1 in /docs

Bumps [devalue](https://github.com/sveltejs/devalue) from 5.6.3 to 5.8.1.
- [Release notes](https://github.com/sveltejs/devalue/releases)
- [Changelog](https://github.com/sveltejs/devalue/blob/main/CHANGELOG.md)
- [Commits](sveltejs/devalue@v5.6.3...v5.8.1)

---
updated-dependencies:
- dependency-name: devalue
  dependency-version: 5.8.1
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]