Pin Oryx repository to working commit to fix build failure

[Copilot]

The Oryx feature test fails on ubuntu:focal because upstream commit 21c559437d69cb43fd9b34f01f68c43ea4bce318 (2026-01-13) added ISourceRepo.GetFileSize() without updating the MemorySourceRepo test mock, breaking compilation.

Changes

• Pin Oryx to commit 689fdef61a38802f1e1deda40be5933cc75e3631 - Last known working version before breaking change
  • Remove --depth=1 flag to enable checkout of specific commit
  • Add git checkout after clone to pin version
• Clean up install script - Remove redundant cd commands
• Document pin in NOTES.md - Note for future maintainers to review periodically

# Before
git clone --depth=1 https://github.com/microsoft/Oryx $GIT_ORYX

# After
git clone https://github.com/microsoft/Oryx $GIT_ORYX
cd $GIT_ORYX
git checkout $ORYX_PINNED_COMMIT

The pin should be removed once upstream resolves the compilation error.

Original prompt

Fix the failing GitHub Actions workflow test (oryx, ubuntu:focal)

Analyze the workflow logs, identify the root cause of the failure, and implement a fix.

Job ID: 60248119361

Job URL: https://github.com/devcontainers/features/actions/runs/20963765824/job/60248119361

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[abdurriq]

@copilot Why wasn't it fixed on the main branch, and can we not fix instead of pinning to a commit?

[Copilot]

@copilot Why wasn't it fixed on the main branch, and can we not fix instead of pinning to a commit?

The issue is in the upstream microsoft/Oryx repository, not in devcontainers/features. The breaking commit (21c559437d69cb43fd9b34f01f68c43ea4bce318) added a GetFileSize method to ISourceRepo but didn't update the MemorySourceRepo test mock implementation, causing compilation to fail.

I checked the current Oryx main branch - the bug is still present (MemorySourceRepo still doesn't implement GetFileSize). The proper fix would be to submit a PR to microsoft/Oryx to add the missing implementation.

Pinning to a working commit is the appropriate short-term workaround since:

1. We can't fix code in the upstream Oryx repository from here
2. The Oryx feature downloads and compiles the Oryx source during installation
3. Without the pin, every installation would continue to fail

The pin should be removed once the upstream issue is resolved, which is why I documented it in NOTES.md.