Sending to a topic based on the number of firing alerts makes no
sense, and leads to conversations and alerts scattered randomly across
topics based on how on fire the alerting is.
Send a separate message for each alert in the Grafana webhook payload,
with the alert's name as its topic; if no alert name can be found,
fall back to the alert's fingerprint. Also include all alert values
in the body of the message, along with links to the alert generator,
silence, and image, if available.
Co-authored-by: Alex Vandiver <alexmv@zulip.com>
Ryan Crisanti