Users can just use std::vector<Global<T>>.

Bug: v8:12915
Change-Id: I59fc8458e336df0dfaa3524f1197d4423482530e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695578Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81023}