This reverts commit 3b05be2fd0.
Reason for revert: Sourcegraph still does not support fetching arbitrary refs, so we'll have to wait until its Gerrit integration lands before this will work correctly.
Change-Id: Icee82c50f92c34ba1741b608449aed16538ccbaa
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2721
Tested-by: BuildkiteCI
Reviewed-by: lukegb <lukegb@tvl.fyi>