Update Bencher CLI usage (#2087)

This changeset updates the Bencher CLI to the new recommended usage.
See: https://bencher.dev/docs/how-to/github-actions/#pull-requests-from-forks

.github/workflows/upload-pr-benchmarks.yaml

@@ -15,43 +15,22 @@ jobs:
       PR_EVENT: event.json
     steps:
       - name: Download Benchmark Results
-        uses: actions/github-script@v7
+        uses: dawidd6/action-download-artifact@v6
         with:
-          script: |
-            async function downloadArtifact(artifactName) {
-              let allArtifacts = await github.rest.actions.listWorkflowRunArtifacts({
-                owner: context.repo.owner,
-                repo: context.repo.repo,
-                run_id: context.payload.workflow_run.id,
-              });
-              let matchArtifact = allArtifacts.data.artifacts.filter((artifact) => {
-                return artifact.name == artifactName
-              })[0];
-              if (!matchArtifact) {
-                core.setFailed(`Failed to find artifact: ${artifactName}`);
-              }
-              let download = await github.rest.actions.downloadArtifact({
-                owner: context.repo.owner,
-                repo: context.repo.repo,
-                artifact_id: matchArtifact.id,
-                archive_format: 'zip',
-              });
-              let fs = require('fs');
-              fs.writeFileSync(`${process.env.GITHUB_WORKSPACE}/${artifactName}.zip`, Buffer.from(download.data));
-            }
-            await downloadArtifact(process.env.BENCHMARK_RESULTS);
-            await downloadArtifact(process.env.PR_EVENT);
-      - name: Unzip Benchmark Results
-        run: |
-          unzip $BENCHMARK_RESULTS.zip
-          unzip $PR_EVENT.zip
+          name: ${{ env.BENCHMARK_RESULTS }}
+          run_id: ${{ github.event.workflow_run.id }}
+      - name: Download PR Event
+        uses: dawidd6/action-download-artifact@v6
+        with:
+          name: ${{ env.PR_EVENT }}
+          run_id: ${{ github.event.workflow_run.id }}
       - name: Export PR Event Data
         uses: actions/github-script@v7
         with:
           script: |
             let fs = require('fs');
             let prEvent = JSON.parse(fs.readFileSync(process.env.PR_EVENT, {encoding: 'utf8'}));
-            core.exportVariable("PR_HEAD", `${prEvent.number}/merge`);
+            core.exportVariable("PR_HEAD", prEvent.pull_request.head.ref);
             core.exportVariable("PR_BASE", prEvent.pull_request.base.ref);
             core.exportVariable("PR_BASE_SHA", prEvent.pull_request.base.sha);
             core.exportVariable("PR_NUMBER", prEvent.number);
@@ -61,12 +40,14 @@ jobs:
           bencher run \
           --project nickel \
           --token '${{ secrets.BENCHER_API_TOKEN }}' \
-          --branch '${{ env.PR_HEAD }}' \
-          --branch-start-point '${{ env.PR_BASE }}' \
-          --branch-start-point-hash '${{ env.PR_BASE_SHA }}' \
+          --branch "$PR_HEAD" \
+          --start-point "$PR_BASE" \
+          --start-point-hash "$PR_BASE_SHA" \
+          --start-point-clone-thresholds \
+          --start-point-reset \
           --testbed ubuntu-latest \
           --adapter rust_criterion \
           --err \
           --github-actions '${{ secrets.GITHUB_TOKEN }}' \
-          --ci-number '${{ env.PR_NUMBER }}' \
-          --file "$BENCHMARK_RESULTS.txt"
+          --ci-number "$PR_NUMBER" \
+          --file "$BENCHMARK_RESULTS.txt"