[Temporal] Minor tweak for code calling temporal parser

Rewrite CreateTemporalTimeZone to sync with
https://github.com/tc39/proposal-temporal/pull/2008



Bug: v8:11544
Change-Id: I75c75146a5a84fc51d4b5ed182641ebf697e8389
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3630351Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80607}