Test that also signal handlers cannot write to code, even if a
{CodeSpaceWriteScope} is open when the signal is triggered.

R=jkummerow@chromium.org
CC=mpdenton@chromium.org

Bug: v8:11974
Change-Id: I1e49e4b31ba196948f7f7adfdf88675816e0a58a
Cq-Include-Trybots: luci.v8.try:v8_mac_arm64_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_mac_arm64_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3140607Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#76747}