Some tests explicitly set the --always-opt flag, but they are not
ignored when the testrunner is invoked with variant="jitless" or
variant="nooptimization".
This CL implies --opt from --always-opt and excludes
--always-opt when the testrunner is invoked with jitless or
nooptimization variants.

Change-Id: I49ebc3907666c462aa09a294a39a504a0c90de96
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2544548Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71258}