[cv] remove logging which is rarely informative.
[cv] remove logging which is rarely informative.

The RM and PM should log at their own level what they consider
necessary.

R=qyearsley, yiwzhang

Change-Id: Iba713119854a354214adb329c10dba613305c78c
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/2968287
Auto-Submit: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>
Commit-Queue: Yiwei Zhang <50b2a565e2e78c292794832469a30ce5abc9959c@google.com>
Reviewed-by: Yiwei Zhang <50b2a565e2e78c292794832469a30ce5abc9959c@google.com>

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go