- Add a SIGTERM handler in d8 that dupms the stack trace
- Send SIGTERM before SIGKILL in the test runner

Bug: v8:13115
Change-Id: I75285f33caabab61ff6ae83c1fbc6faf45cf595a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3791906Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82173}