Turn on fuzzing to get additional test coverage.

Bug: v8:12578
Change-Id: Ia614fb9e4ba519163024f3b7b40f22ad6ebb3297
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3442677Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78977}