.github/workflows: Migrate workflows to Blacksmith runners

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Blacksmith is the fastest way to run your GitHub Actions.

What does this PR change?

This PR has been automatically generated by a team member in your GitHub organization using Blacksmith's Migration Wizard, or MigWiz for short. This PR changes the following:

1. Your selected workflows will now run on Blacksmith's 2x faster hardware (e.g., runs-on: blacksmith-4vcpu-ubuntu-2204). Learn more about the different instances available to choose from.
2. Your jobs running on Blacksmith will now have all official GitHub and popular third-party cache actions automatically interact with our 4x faster, colocated cache. Learn more about Blacksmith's actions cache.
3. Your GitHub Actions will now actually be observable. Learn more about Blacksmith's logging and other observability features.
4. Your Docker builds will now automatically share their Docker layer cache, resulting in up to 40x faster builds. Learn more about Blacksmith's Docker layer caching.

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• What's the catch? There is none. Merge this thing already.

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Matrix OS partially migrated, leaving ubuntu-22.04 unmigrated

Low Severity

The matrix os list and include entries only migrated ubuntu-latest to blacksmith-4vcpu-ubuntu-2404 but left ubuntu-22.04 as a standard GitHub runner. This repository already uses blacksmith-4vcpu-ubuntu-2204 in test-buildkit-version.yml, so ubuntu-22.04 here is an incomplete migration. Half the matrix jobs will run on GitHub's standard runners instead of Blacksmith, which is inconsistent with the PR's intent and could fail if the org restricts runner usage.

Additional Locations (1)

• .github/workflows/docker-stress-test.yml#L211-L213

 

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