Use grep to check for obviously unneeded includes. e.g. headers that
include <vector> but does not contain "std::vector".

Change-Id: I43a9e9f01e072fd495918d28ca4cdad5cfa0294c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3354400Reviewed-by: Marja Hölttä <marja@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78613}