[Fuchsia] common.catch_sigterm to ensure the process can catch the sigterm

Without using signal.signal, `kill` command can kill the process without
notifying the following catch statements.

Bug: 1411345
Change-Id: Ia3304f76b1272a144e536dddc6d913bb9e0ed03d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4343613


Commit-Queue: Zijie He <zijiehe@google.com>
Reviewed-by: Chong Gu <chonggu@google.com>
Commit-Queue: Chong Gu <chonggu@google.com>
Cr-Commit-Position: refs/heads/main@{#1118882}