Bump dawidd6/action-download-artifact from 6 to 8

Bumps [dawidd6/action-download-artifact](https://github.com/dawidd6/action-download-artifact) from 6 to 8.
- [Release notes](https://github.com/dawidd6/action-download-artifact/releases)
- [Commits](dawidd6/action-download-artifact@v6...v8)

---
updated-dependencies:
- dependency-name: dawidd6/action-download-artifact
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/pr-benchmark-upload-from-main.yml

@@ -17,12 +17,12 @@ jobs:
       PR_EVENT: event.json
     steps:
       - name: Download Benchmark Results
-        uses: dawidd6/action-download-artifact@v6
+        uses: dawidd6/action-download-artifact@v8
         with:
           name: ${{ env.BENCHMARK_RESULTS }}
           run_id: ${{ github.event.workflow_run.id }}
       - name: Download PR Event
-        uses: dawidd6/action-download-artifact@v6
+        uses: dawidd6/action-download-artifact@v8
         with:
           name: ${{ env.PR_EVENT }}
           run_id: ${{ github.event.workflow_run.id }}