[Robustness] Hard to find a report from failing tests as artifacts have empty directories for all tests

[serathius]

Bug report criteria

• This bug report is not security related, security issues should be disclosed privately via security@etcd.io.
• This is not a support request or question, support requests or questions should be raised in the etcd discussion forums.
• You have read the etcd bug reporting guidelines.
• Existing open issues along with etcd frequently asked questions have been checked and this is not a duplicate.

What happened?

If you open results.zip for any robustness tests like https://gcsweb.k8s.io/gcs/kubernetes-ci-logs/logs/ci-etcd-robustness-main-s390x/1962827218790912000/artifacts/
It's full of empty directories for successful tests.

What did you expect to happen?

There should just one directory for the failed tests making it easy to find.

How can we reproduce it (as minimally and precisely as possible)?

Download any results.zip file from robustness tests prow https://testgrid.k8s.io/sig-etcd-robustness#ci-etcd-robustness-main-amd64

Anything else we need to know?

No response

Etcd version (please run commands below)

$ etcd --version
# paste output here

$ etcdctl version
# paste output here

Etcd configuration (command line flags or environment variables)

paste your configuration here

Etcd debug information (please run commands below, feel free to obfuscate the IP address or FQDN in the output)

$ etcdctl member list -w table
# paste output here

$ etcdctl --endpoints=<member list> endpoint status -w table
# paste output here

Relevant log output