New metric for when CT GCE bots should be checked for BotMissing alerts
New metric for when CT GCE bots should be checked for BotMissing alerts

Bug: skia:6648
Change-Id: I792f3726efebd7b3e8d957fb95b0a673d397c810
Reviewed-on: https://skia-review.googlesource.com/28781
Reviewed-by: Ben Wagner <3ef7217be91069877d94f7907ce5479000772cd3@google.com>
Commit-Queue: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot