Add timeout to artifact uploads

When artifact uploads hang (in the incident it was due to a haproxy regression), we never time out. This resulted in all jobs that upload artifacts hanging until the job timeout.

That wastes job minutes for us and our customers.

We should put some reasonable timeout in place here. We can make it overridable.

This would be baked into gitlab-runner-helper.

This ticket was created from INC-4485 and was automatically exported by incident.io 🔥