Disable a flaky test.

This is a reland of cbf028e8

Original change's description:
> [Heap] Create a fast path for young allocations.
>
> Bug: v8:9714
> Change-Id: I3be6ea615142c8282bb67370626c7596cedf826c
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1800304
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Commit-Queue: Victor Gomes <victorgomes@google.com>
> Auto-Submit: Victor Gomes <victorgomes@google.com>
> Cr-Commit-Position: refs/heads/master@{#63729}

Bug: v8:9714
Change-Id: Ifbd8617be1b8c58cb1552fe88c52eafd9d6e9c7d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1801840
Commit-Queue: Victor Gomes <victorgomes@google.com>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Victor Gomes <victorgomes@google.com>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63744}