https://github.com/tc39/proposal-temporal/pull/2260

Spec text:
https://tc39.es/proposal-temporal/#sec-temporal-getoffsetnanosecondsfor

Bug: v8:11544
Change-Id: I107372ba883f97c1bf74b96cd0f592d47aa1f359
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3901199
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#83376}