Drain the CQ starting at 11AM PST for emergency lab network maintenance.

Maintenance will last about an hour. Drain the CQ for the duration of
this.

NOTRY=true
TBR=jbudorick, tandrii

Change-Id: Ic5114c910c431ddd92cacfc323d7cd420cc9657a
Reviewed-on: https://chromium-review.googlesource.com/1255222Reviewed-by: Ben Pastene <bpastene@chromium.org>
Reviewed-by: John Budorick <jbudorick@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#595479}

infra/config/branch/cq.cfg

@@ -10,7 +10,7 @@ max_commit_burst: 2
 # Trooper, if you want to drain CQ such that CQ stops triggering new trybots,
 # uncomment line below. The timestamp cutoff time in UTC s.t. all CLs
 # on which CQ was triggered **after** this time are ignored by CQ.
-# draining_start_time: "2018-02-28T20:00:00Z"
+draining_start_time: "2018-10-01T18:00:00Z"
 
 gerrit {}