fix download check

[ewlu]

One of kevin's changes was that the download_artifact.py script now immediately extracts the values into the output directory. However, we didn't update the change to the downtime runner so the logs show

Run mkdir result
  mkdir result
  mkdir temp
  python ./scripts/download_artifact.py -name "downtime_runner_success" -repo ewlu/gcc-precommit-ci -token *** -outdir result || true
  ls result
  shell: /usr/bin/bash -e {0}
  env:
    pythonLocation: /opt/hostedtoolcache/Python/3.11.13/x64
    PKG_CONFIG_PATH: /opt/hostedtoolcache/Python/3.11.13/x64/lib/pkgconfig
    Python_ROOT_DIR: /opt/hostedtoolcache/Python/3.11.13/x64
    Python2_ROOT_DIR: /opt/hostedtoolcache/Python/3.11.13/x64
    Python3_ROOT_DIR: /opt/hostedtoolcache/Python/3.11.13/x64
    LD_LIBRARY_PATH: /opt/hostedtoolcache/Python/3.11.13/x64/lib
##[debug]Overwrite 'working-directory' base on job defaults.
##[debug]/usr/bin/bash -e /home/runner/work/_temp/820b727b-228b-[45](https://github.com/ewlu/gcc-precommit-ci/actions/runs/17198138561/job/48783568251#step:7:45)90-898f-61215c96dbfb.sh
download for downtime_runner_success: 200
end_date.txt <-- ls result output

causing this check if ( test -f result/downtime_runner_success ); then to fail. This resulted in the downtime runner never actually doing anything