The bulk-memory proposal and the reference types proposal have been
merged into the main repository, so we don't have to run the proposal
tests anymore.

R=ecmziegler@chromium.org

Change-Id: I14583b8c1c387075442a402458ce04e7c6071f89
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2752165
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Emanuel Ziegler <ecmziegler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73481}