Missing parameter for alarm logger in the documentation

[lcaouen]

The following parameter is missing in the documentation (https://epics-extensions.github.io/EPNix/nixos/guides/phoebus-alarm.html#enabling-the-phoebus-alarm-services) :

services.phoebus-alarm-logger.settings."bootstrap.servers" = "${kafkaSock}";

This parameter is necessary if kafka is configured to listen to a different ip than localhost
Could you add it ?

[minijackson]

Done in #60