Roll luci-go/isolate to 1f9e1c67c47e9801d9eae588c8c13adcb9baa077.

This fixes one non-determinism in the .isolated.

TBR=tandrii@chromium.org
BUG=314403

Review URL: https://codereview.chromium.org/1314453002

Cr-Commit-Position: refs/heads/master@{#344983}
3 files changed