[rts] Fix logging of lost patchsets
[rts] Fix logging of lost patchsets

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R=tandrii@chromium.org

Bug: 1112125
Change-Id: I9b6661640ed79d2ee097e243c909f6c9f292c6cc
Reviewed-on: https://chromium-review.googlesource.com/c/infra/luci/luci-go/+/2462681
Auto-Submit: Nodir Turakulov <ef4933a197ef7b4b3f55f1bec4942aead3637a2a@chromium.org>
Commit-Queue: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>
Reviewed-by: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@google.com>

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