rsnapshot-push: 1-hour SSH timeout before ending the backup session

The default timeout on the Copr Backend server is set to 60 seconds,
which can sometimes trigger the cancellation of the backup process.

roles/rsnapshot-push/templates/client-backup-script.sh.j2

@@ -5,5 +5,6 @@
 exec rsync -av --xattrs --acls \
     --delete --delete-excluded \
     --rsh=ssh \
+    -e 'ssh -o ConnectTimeout=3600' \
     {{ item.value.rsync_args }} \
     {{ item.value.user }}@{{ rsnapshot_push.server_host }}::push