Bump actions/upload-artifact from 2 to 4 (#545)

Bumps [actions/upload-artifact](https://github.com/actions/upload-artifact) from 2 to 4.
- [Release notes](https://github.com/actions/upload-artifact/releases)
- [Commits](actions/upload-artifact@v2...v4)

---
updated-dependencies:
- dependency-name: actions/upload-artifact
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Simone Carlo Surace <[email protected]>

Author: dependabot[bot]

.github/workflows/benchmark.yml

@@ -47,7 +47,7 @@ jobs:
       - name: record pull request number
         run: echo ${{ github.event.pull_request.number }} > ./pull-request-number.artifact
       # save as artifacts (performance tracking (comment) workflow will use it)
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@v4
         with:
           name: Benchmarking
           path: ./*.artifact