Bump actions/download-artifact from 4 to 5 (#2311)

Bumps
[actions/download-artifact](https://github.com/actions/download-artifact)
from 4 to 5.

- vLLM version: v0.10.0
- vLLM main:
ebf7605b0d

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/accuracy_test.yaml

@@ -261,7 +261,7 @@ jobs:
           git checkout -B "${BRANCH_NAME}" upstream/main
 
       - name: Download only current run reports
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v5
         with:
           path: ./docs/source/developer_guide/evaluation/accuracy_report
           pattern: report-*