bake: deduplicate context transfer use case

[crazy-max]

follow-up https://github.com/docker/docs/pull/20245#pullrequestreview-2135178926

Description

Add use case to avoid duplicated context transfer when using multiple targets with bake.

cc @tonistiigi @dgageot @caervs

Related issues or tickets

• https://github.com/docker/buildx/issues/92
• https://github.com/docker/buildx/issues/1377

Reviews

• [x] Technical review
• [x] Editorial review
• [ ] Product review

[netlify[bot]]

✅ Deploy Preview for docsdocker ready!

Name	Link
🔨 Latest commit	439e0b7cd29a30af0e60fbe2d7dad664eb31d238
🔍 Latest deploy log	https://app.netlify.com/sites/docsdocker/deploys/667a839a4ddcf500081fccca
😎 Deploy Preview	https://deploy-preview-20282--docsdocker.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.