These tests became flaky with multi-process.

Bug: angleproject:5172
Change-Id: I6ede6b33f8c2ddfb3970fbc2b7586c7622b79a09
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2482293Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>