Use sigint instead of sighup to stop gerrit

The old gerrit init script uses sighup to request a graceful shutdown
of the service which is why when we ported to docker-compose we
configured it to also use sighup. Unfortunately, on noble with podman
the podman container apparmor profiles don't allow podman to issue a
sighup to the container. This means when we try to stop the service we
wait until the 5 minute timeout expires then docker compose + podman
issue a sigkill.

This is less graceful than we want. To address this we switch to sigint
instead. The reason for this is the podman container apparmor profiles
do allow signit and the jvm appears to treat sigint, sigterm, and sighup
as equivalent triggers for the shutdown hook.

Change-Id: Iacfc70713d63443d58bb563b895fdc5dfb0642e2

playbooks/roles/gerrit/templates/docker-compose.yaml.j2

@@ -25,7 +25,7 @@ services:
     command: ["/wait-for-it.sh", "127.0.0.1:3306", "--", "/run-gerrit.sh"]
     network_mode: host
     user: gerrit
-    stop_signal: SIGHUP
+    stop_signal: SIGINT
     stop_grace_period: 5m
     volumes:
 {% for volume in gerrit_container_volumes %}