Fixes git workspace after checking out benchmarks

[alganet]

With the introduction of composite actions in the GitHub workflows, the ci-perf.yml workflow broke.

This happens because the setup-action configures a Post Run (a hook to be executed after the workflow).

Since the benchmarks checkout a different orphan branch, when that Post Run executes, it cannot find the action anymore.

To fix it, I introduce a new step that restores the git workspace, making it available for that hook.

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Example failure:

https://github.com/Respect/Validation/actions/runs/21448771339/job/61772437584

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.03%. Comparing base (b69beb1) to head (b5e3258).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #1636   +/-   ##
=========================================
  Coverage     98.03%   98.03%           
  Complexity      961      961           
=========================================
  Files           197      197           
  Lines          2234     2234           
=========================================
  Hits           2190     2190           
  Misses           44       44           

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[Copilot]

Pull request overview

Fixes ci-perf.yml failures caused by checking out the benchmarks orphan branch, which breaks subsequent post-run hooks for local/composite actions by restoring the workspace back to the original commit.

Changes:

• Adds an always-run step to restore the git workspace to ${GITHUB_SHA} after pushing benchmark results.

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[henriquemoody]

I'm not absolutely sure, but isn't this what actions/checkout@v6 does? Perhaps we could use it also at the start of the job to checkout the benchmarks branch?

[alganet]

@henriquemoody

If we checkout only the benchmarks branch, there will be no vendor/bin/phpbench or benchmark classes to run.

I need to first checkout the codebase, run the benchmarks, then checkout the benchmarks and update it with the results.

Perhaps there are better ways of doing it, but I could not find them.

I know for sure this restore works because I did it in the PHL repository (it has a similar coverage branch also with composite actions): https://github.com/alganet/PHL/blob/main/.github/workflows/build.yml#L170

Perhaps we can do another checkout at the end, but I never tried that.

[henriquemoody]

I suggested using actions/checkout@v6 so you didn't have to run those Git commands in so many places, and just using actions/checkout@v6 to handle that. You can use it into different paths with different branches, but it's not an issue, using the git commands is just fine.

[alganet]

I can confirm the fix worked as intended: