Fail build if artifacts fail to download or extract
We saw in gitlab-org/release/tasks#235 (comment 76027230) that the runner continued with the job even though it ran out of space while extracting the artifacts ZIP file:
WARNING: pkg/ubuntu-xenial/gitlab-ee_10.8.3-ee.0_amd64.deb: write pkg/ubuntu-xenial/gitlab-ee_10.8.3-ee.0_amd64.deb: no space left on device (suppressing repeats)
In this case, we should either fail the build or clean up after the extraction. The latter doesn't seem that straightforward because a ZIP file can write to many places.