v2.9.15-canary.6

<!-- Release notes generated using configuration in .github/release.yml at v2.9.15-canary.6 -->

What's Changed

Changelog

• release(turborepo): 2.9.15-canary.5 by @github-actions[bot] in https://github.com/vercel/turborepo/pull/12919
• fix: Restore task completion semantics by @anthonyshew in https://github.com/vercel/turborepo/pull/12923
• fix: Preserve nested Bun workspace dependency versions by @anthonyshew in https://github.com/vercel/turborepo/pull/12924

Full Changelog: https://github.com/vercel/turborepo/compare/v2.9.15-canary.5...v2.9.15-canary.6