This flag is now enabled by default for quite some time in production.
In addition that flag was already defined readonly and couldn't be
disabled, so let's remove this flag for good.

Bug: v8:10064
Change-Id: I0e71eee9d25960a96324d56c8f0191fe678dc6e6
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3268907
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77806}