Some follow-up after getting rid of `let`.

Change-Id: I073372f4edd0847c4ffa428595a6f74158c87a98
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3773515Reviewed-by: Manos Koukoutos <manoskouk@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81844}