ci: Fix build-test-publish summary job always passing

[ko3n1g]

Summary

• SKIPPING_IS_ALLOWED was hardcoded to true in the summary job, causing it to always exit 0 regardless of actual job outcomes
• This masked failures in matrix jobs (e.g. the arm64 build job in Add torch grouped gemm bf16 and mxfp8 support w/ cuda graphed + inference_optimized MoEs #3858)
• Fixed by setting SKIPPING_IS_ALLOWED: false since build-test-publish-wheels has no if condition that would legitimately skip it

Test plan

• Verify the summary job correctly fails when a matrix job (arm64/amd64) fails
• Verify the summary job passes when all jobs succeed

🤖 Generated with Claude Code

[github-actions]

This PR has been automatically converted to draft because all PRs must start as drafts.

When you are ready for review, click Ready for Review to begin the review process. This will:

1. Add the oncall reviewer (optional reviewer)
2. Add required review teams based on your changes

See the contribution guide for more details.

[copy-pr-bot]

Auto-sync is disabled for draft pull requests in this repository. Workflows must be run manually.

Contributors can view more details about this message here.