Remove chrome proxy ChromeDriver tests that do not run below M70

Change-Id: Ib23cebb278918266ffe3822d3458e67fc55dfbf1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1584599
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Commit-Queue: Robert Ogden <robertogden@chromium.org>
Cr-Commit-Position: refs/heads/master@{#654107}
4 files changed