Revert of [cq] Increase commit burst delay. (patchset #1 id:1 of https://codereview.chromium.org/1258193003/)

Reason for revert:
Committing more than one CL at a time led to some odd buildbot behavior on the console (probably an independent bug).

Original issue's description:
> [cq] Increase commit burst delay.
>
> TBR=jkummerow@chromium.org, hablich@chromium.org
> NOTRY=true
> NOTREECHECKS=true
>
> Committed: https://crrev.com/1f2e914d103532df410f118c81c60fba8b6a00e0
> Cr-Commit-Position: refs/heads/master@{#29914}

TBR=jkummerow@chromium.org,hablich@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1263183002

Cr-Commit-Position: refs/heads/master@{#29944}

TBR=jkummerow@chromium.org, hablich@chromium.org
NOTRY=true
NOTREECHECKS=true

Review URL: https://codereview.chromium.org/1258193003

Cr-Commit-Position: refs/heads/master@{#29914}

Currently this verifier will post an informative error if the author has not signed CLA, instead of rejecting the CL.

LOG=N

BUG=457428

Review URL: https://codereview.chromium.org/1185193009

Cr-Commit-Position: refs/heads/master@{#29096}

This will land with https://chromereviews.googleplex.com/202967013

R=akuegel@chromium.org, machenbach@chromium.org
BUG=471767
NOTRY=true
LOG=N

Review URL: https://codereview.chromium.org/1161873004

Cr-Commit-Position: refs/heads/master@{#28684}