skylab_test_runner: Add is_client_test and display_name

BUG=chromium:1031938
TEST=./generate.sh

Change-Id: If5e93298a246d945a83a7c070c8e5f14cdfea508
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/1961057
Tested-by: Alex Zamorzaev <zamorzaev@chromium.org>
Auto-Submit: Alex Zamorzaev <zamorzaev@chromium.org>
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Commit-Queue: Alex Zamorzaev <zamorzaev@chromium.org>
3 files changed