Using curl to POST to the CircleCI workflow endpoint on CZO:
- Doesn't work on zulip/zulip@main (CZO runs a revert)
- Sets a bad example for other orgs
- Robs us of an opportunity to dogfood our own zulip/github-actions-zulip
Refactor the Actions workflows in this repo to report failure states
using the Zulip Action, and reimplement the related helper scripts in
Python, since they'd previously mostly shelled out to Python anyway.
Josh Klar