Checkmk Werk 14745: Fix "Data: b''" in notification result of event console bulk notifications

ID: 14745 Title: Fix "Data: b''" in notification result of event console bulk notifications Component: Notifications Level: 1 Class: Bug fix Version: 2.2.0i1 The event console can send notifications with the option "Send monitoring notification" in an event console rule enabled. If such rule matched and a notification rule with bulk enabled matched that notification, the notification result could contain, in addition to successful processing, the entry "Data: b''". This happend if no graph could be found for the host or service of the notification. This problem exists at least since version 1.6. Also a traceback with multiple exceptions was shown in ~/var/log/web.log.