Stop the OVN database during the cleanup script

Stop the DB server gracefully; this will also end the pod running script.
By executing the stop command in the backgroung, we guarantee to exit
this script and not fail with "FailedPreStopHook", while the database is
stopped and the pod exits.

Closes-Issue: OSPRH-8118

templates/ovndbcluster/bin/cleanup.sh

@@ -44,3 +44,9 @@ if [[ "$(hostname)" != "{{ .SERVICE_NAME }}-0" ]]; then
     # now that we left, the database file is no longer valid
     cleanup_db_file
 fi
+
+# Stop the DB server gracefully; this will also end the pod running script.
+# By executing the stop command in the background, we guarantee to exit
+# this script and not fail with "FailedPreStopHook", while the database is
+# stopped.
+/usr/share/ovn/scripts/ovn-ctl stop_${DB_TYPE}_ovsdb &