Allow test picker to pick a test that also has subtests.
Allow test picker to pick a test that also has subtests.

Bug: chromium:1039589
Change-Id: Ie413fab2b71f654d8edf9fc134231b93f1bbbc7d
Reviewed-on: https://chromium-review.googlesource.com/c/catapult/+/2100051
Commit-Queue: Dean Berris <34a37f59e4ade3cf49221306f04217acf3e86255@chromium.org>
Reviewed-by: Dean Berris <34a37f59e4ade3cf49221306f04217acf3e86255@chromium.org>

catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult,catapult-project/catapult