findmissing: reduce spurious log

Print the "Finding" message only if it finds new rows.

BUG=b:223717399
TEST=./scripts/gce/full_sync_and_patch_create.sh

Change-Id: I01f086c656428d75d9e48707d7a920b9e12d7bff
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/3949192
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Tested-by: Tzung-Bi Shih <tzungbi@chromium.org>
Commit-Queue: Tzung-Bi Shih <tzungbi@chromium.org>
1 file changed