Revert "Add luci-go tool to be fetched via CIPD"

This reverts commit 3bcc71d83f6d9af93a7408fbea34f6d5f0185c03.

Reason for revert: appears to break official builds due to how the cipd variable is flattened.

Original change's description:
> Add luci-go tool to be fetched via CIPD
> Do not remove the adhoc mechanism on GCS that predates CIPD yet, as the recipes
> need to be updated.
> Change analyze to not ignore changes to isolate.
> R=‚Äč
> Bug: 851596
> Change-Id: Ic068db83dea4c3a0f17b55181de523b16c9838a5
> Reviewed-on:
> Commit-Queue: Andrii Shyshkalov <>
> Reviewed-by: Andrii Shyshkalov <>
> Reviewed-by: John Budorick <>
> Cr-Commit-Position: refs/heads/master@{#569688},,,

# Not skipping CQ checks because original CL landed > 1 day ago.

No-Presubmit: true
Bug: 851596
Change-Id: I3717c6b0ebf68b08908037850d122727e41bf192
Commit-Queue: John Budorick <>
Reviewed-by: John Budorick <>
Cr-Original-Commit-Position: refs/heads/master@{#569938}
Cr-Mirrored-Commit: 0c062061326cd05a1ab884e5b2d6e03e2b79f215
3 files changed