[k8s-deployer] Fix closure when downloading files
[k8s-deployer] Fix closure when downloading files

Bug: skia:12544
Change-Id: I5a474782ce542d99eef2dfb3a41d1e955c6549ed
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/548681
Auto-Submit: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>
Commit-Queue: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>
Reviewed-by: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot