[repo] ensure we don't restart a task while the repo is shutting down (closes #1942736)
we need a safety belt in cw itself again looping task which use 'try / except'
or doesn't need to access the db (which will trigger ShuttingDown exception)
#! /bin/sh -e
if [ -x "/etc/init.d/cubicweb-ctl" ]; then
invoke-rc.d cubicweb-ctl restart || true
fi
#DEBHELPER#
exit 0