Please fix closed but unfixed issue

[paulfi94]

Is your feature request related to a problem? Please describe.
#615 was closed but not fixed.

Describe the solution you'd like
The customer needs to be able to subscribe to Monitors on the Public Status page so he gets a Notification when the Monitors are added to an Incident or that incident is updated.

[Gunni]

I am also missing the Subscribe to Monitors feature!

[Gunni]

This and the incorrectly closed ticket are blocked blocking the onboarding of this system for my company.