[CI] Run postcommit for pulldown PRs

[sarnex]

We need to run postcommit in pulldown PRs.

In this PR the job is running twice, once for the push action and once for pull_request since we modified the postcommit workflow, but in a normal pulldown won't happen.

We can't use the pull_request action because GitHub requires both branches and paths to be satisfied which won't be true for a normal pulldown.

See #22620

[sarnex]

CI fails not related

[jsji]

I think this will cause dup run in pulldown PR, we removed it intentionally in a8ab2bb . But hopefully something has changed. Let us see.

[sarnex]

I can't see how pull_request would get triggered since none of the required files would be modified, but yeah who knows let's see

[jsji]

https://github.com/intel/llvm/actions/workflows/sycl-post-commit.yml?query=branch%3Allvmspirv_pulldown

We can see in the history that post-commit was being run every time before WW23 2026, just skipped in last two PRs WW25 and WW28.

In WW23's workflow file https://github.com/intel/llvm/actions/runs/27094331837/workflow , there was no llvmspirv_pulldown in push either. Not sure how it was triggered.

Probably a github CI bug just fixed recently? https://github.blog/changelog/2026-06-18-control-who-and-what-triggers-github-actions-workflows/ just between WW23 and WW25.

[sarnex]

Thanks for the investigation, if I understand your analysis correctly the current change merged in this PR seems okay for the current GitHub CI state. If I'm wrong and I need to fix/revert something let me know