These tests rely on predictable opt & deopt timings. Also add the
--opt flag to tests to force optimization even in configurations that
contain the --no-opt flag.

Bug: v8:9972,chromium:1049982
Change-Id: Ic161d188ebfae9aaae6a160d365413abedfee5f1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2050402Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66231}