v2.8.3-canary.12

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What's Changed

Changelog

• chore: Upgrade reqwest toward addressing RUSTSEC-2025-0134 by @anthonyshew in https://github.com/vercel/turborepo/pull/11718
• fix(docs): Fix code syntax highlighting by using correct Shiki CSS variable names by @anthonyshew in https://github.com/vercel/turborepo/pull/11726
• fix: Upgrade async-io to 2.x to drop unmaintained instant crate by @anthonyshew in https://github.com/vercel/turborepo/pull/11719

Full Changelog: https://github.com/vercel/turborepo/compare/v2.8.3-canary.11...v2.8.3-canary.12