Network Service: Remove loading.desktop.network_service benchmark

The loading.desktop.network_service performance benchmark needs to be
removed since this style of benchmark is not supported in Telemetry.
The network service performance on desktop can be monitored by the
regular loading.desktop benchmark.

Bug: 937933
Change-Id: I135b5987e6c69d8f4e34bd19ed8254b96b7b845b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1506478
Reviewed-by: Simon Hatch <simonhatch@chromium.org>
Reviewed-by: Caleb Rouleau <crouleau@chromium.org>
Commit-Queue: Jun Cai <juncai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638824}
5 files changed