Notification endpoint configurations are not updated unless notification rules change

[adrian-thurston]

The alerting UI suffers from a problem whereby changes to the configuration of a notification endpoint are not reflected in the running system unless a notification rule is also changed.

Steps to reproduce:

1. Alter a notification endpoint configuration of an established setup.

Expected behavior:

Configuration changes are reflected in the running system.

Actual behavior:

Changes do not take effect unless the notification rule configuration is also changed.