[infra] Update alert messages to account for lucicfg
[infra] Update alert messages to account for lucicfg

Bug: skia:11820
Change-Id: I81a68e756f941c579a6c7814dbe155c9d307c50e
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/412999
Reviewed-by: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@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