v2.8.21-canary.13

<!-- Release notes generated using configuration in .github/release.yml at v2.8.21-canary.13 -->

What's Changed

Changelog

• fix: Avoid setsid() in PTY spawn to prevent macOS Gatekeeper CPU spikes by @anthonyshew in https://github.com/vercel/turborepo/pull/12452

Full Changelog: https://github.com/vercel/turborepo/compare/v2.8.21-canary.12...v2.8.21-canary.13