Also add the basic version of GetIANATimeZoneEpochValue AO which only
implement UTC. Verison to support other TimeZone will come later w/ intl
work which depends on ICU.

Spec Text:
https://tc39.es/proposal-temporal/#sec-temporal.timezone.prototype.getpossibleinstantsfor
https://tc39.es/proposal-temporal/#sec-temporal-getianatimezoneepochvalue

Bug: v8:11544
Change-Id: Ib603530d1c70f7a2b85691860a815d44b48eece2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3624980
Commit-Queue: Frank Tang <ftang@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80406}