This allows the tests to continue running on the gc fuzzers while
staying compatible with the --force-slow-path flag being passed
randomly.

When run in slow_path variants these tests are no-ops, but that's
negligible as the tests are also fast without slow_path.

Change-Id: I461c47b669b163e1e1594ea1a941f63e90f2221e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1910947Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64914}