This was triggered by the inspector fuzzer, which terminates execution
after two seconds. This is done by triggering a termination exception
via an interrupt. In this case, the runtime function should return
immediately, and return the exception sentinel.
This CL fixes the WasmDebugBreak runtime function to do that correctly.

R=thibaudm@chromium.org

Bug: chromium:1215711
Change-Id: Idf8e9769809f135b426e4d1a0ef82fae826050b4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3041423Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75838}