Describe the feature request

Hi 👋

I've been using the heartbeat feature for some time now and I was curious if you'd be open to adding a grace-period option?

external-endpoints:
  - name: Heartbeat
    token: xyz
    heartbeat:
      interval: 5m
      grace-period: 30s

Why do you personally want this feature to be implemented?

Right now I need to have my webhook heartbeat gatus every 2m30s, for a 5m interval. It would be much better if I could tell gatus to have a 30s (or whatever) wait on the interval. That means I can keep my webhooks interval to 5m but gatus won't report it as down if the heartbeat came in a few seconds too late.

How long have you been using this project?

3y

Additional information

One could argue why not set the interval to 5m30s and have the webhook configured to send every 5m and that would effectively mean the same thing. However this is more about lining up the intervals in gatus and on the webhook for UX, while having a specific option for a grace period.