[cv] fix queue name for purging.
[cv] fix queue name for purging.

It helps to have equal strings in queue.yaml and tq.AddHandler🤦

R=qyearsley, yiwzhang

Change-Id: I5161e9395dc550eb3c1e2c772f1ff8f68a2e9d51
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/2749257
Auto-Submit: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>
Reviewed-by: Yiwei Zhang <50b2a565e2e78c292794832469a30ce5abc9959c@google.com>
Commit-Queue: Yiwei Zhang <50b2a565e2e78c292794832469a30ce5abc9959c@google.com>
Commit-Queue: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>

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