Waiting for a background thread to finish a task isn't going to
work when there are no background threads. Luckily, we can sidestep
the problem by compiling with Turbofan immediately, instead of
triggering dynamic tier-up through repeated execution. As a nice bonus,
this makes the test faster in non-predictable modes too.

Fixed: v8:13020
Change-Id: I2d47bc07bbde48a210c6ea59551ae16e63bdae05
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3736443Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81459}