fix sed issue

ee/cli/plugins/site.py

@@ -1344,7 +1344,7 @@ class EESiteUpdateController(CementBaseController):
                             Log.error(self, "service nginx reload failed. "
                                  "check issues with `nginx -t` command")
                         Log.info(self,"Removing Cron Job set for cert auto-renewal")
-                        EECron.remove_cron(self,'ee site update {0} --le=renew --min_expiry_limit 30 2> /dev/null'.format(ee_domain))
+                        EECron.remove_cron(self,'ee site update {0} --le=renew --min_expiry_limit 30 2> \/dev\/null'.format(ee_domain))
                         Log.info(self, "Successfully Disabled SSl for Site "
                          " http://{0}".format(ee_domain))