Remove calls to deprecated blobstore API from chromium-build-logs app
Remove calls to deprecated blobstore API from chromium-build-logs app

This was just dead code.

BUG=502036

Review URL: https://codereview.chromium.org/1192343002

nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra