This change includes the following commits from the infra/infra
repository:

$ git log --format='%h %s (%ae)' \
    97ee9cecaac4d99be09278169f987e61b8116672..HEAD \
    -- go/src/infra/chromeperf/pinpoint/cli

a16d4a5458 Fix deadlock in Pinpoint CLI Unit Test (heiserya@google.com)
211e030fbe Add ability to run a batch of experiments to Pinpoint CLI (heiserya@google.com)
ca40b45ace pinpoint: Make artifact download concurrent (dberris@google.com)
08ea607681 pinpoint: print absolute path for downloaded files (fancl@chromium.org)
128352a9fb chromeperf: Add go_package option to protos (dberris@google.com)
6f69cd0a52 pinpoint: Initial support for downloading job artifacts (fancl@chromium.org)
fbcd876092 pinpoint: Compact job listing UI (dberris@google.com)
095bfe3bc8 pinpoint: Set a user agent for the CLI (dberris@google.com)

Change-Id: I4c31857272591667af5587ec83f3418cb1c14303
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2896109
Auto-Submit: Chenlin Fan <fancl@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@google.com>
Commit-Queue: Dirk Pranke <dpranke@google.com>