It's flaky and distracting.

I'm not sure what it's testing, either. It hasn't saved us before.

Somebody can resurrect it if they have time.

Updates #15157

Change-Id: I27bbfe51e09b6259bba0f73d60d03a4d38711951
Reviewed-on: https://go-review.googlesource.com/40498Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>