[HDX-1825] When alert is resolved, HyperDX doesn't send any generic webhook

[demorgi]

See example from Grafana: https://grafana.com/docs/grafana/latest/alerting/configure-notifications/manage-contact-points/integrations/webhook-notifier/

One of the major issue with HyperDX alerting system is that there is no webhook when alert is being resolved when using generic webhooks, making it impossible to auto resolve in different third party alert tracking systems. I think the simpliest way to resolve this is to add an additional input field in webhook configuration (would be nice if that was editable) to specify a template to fire when alert is resolved.

_HDX-1825