Game Server monitors not triggering alerts

[RestartB]

Describe the bug
I've created a Minecraft game server monitor to alert me when my server goes down. I've added the monitor and then shut down my server to test it out. While I can see in the status page that the server is showing as down, the alert is not sent to my Discord webhook trigger.

To Reproduce
Steps to reproduce the behaviour:

1. Add a game server monitor with type set to Minecraft
2. Create an alert that sends when server goes down
3. Cause server to go down
4. Check monitoring data / status page, ensure server is showing as down
5. See that no alert is sent

Version
v4.0.9

Environment
docker

Database
sqlite

Expected behaviour
The alert is sent when the server goes down and when it comes back online.