## Is your feature request related to a problem?
See [this](https://github.com/PostHog/posthog/pull/9139/files/2754c0fd6633c806def5c328d491421ae7de0c19#diff-7f0217a57a02b6ebd709f6aa7bf43760b2d5a53069aee2b7fea27fdad1caadf1) for more info.


## Describe the solution you'd like

> This is used by django-rest-hooks, the library we use to integrate with Zapier. Specifically, this fires our Zapier integration's Triggers. However, the only trigger that actually matters is the "action_performed" one, and that has been completely delegated to the plugin server for a while. We can remove this Python cruft then, along with django-rest-hooks, but first we need to make sure action_defined and annotation_created actually are unused, and roll out an update to https://github.com/PostHog/posthog-zapier that'd remove those two completely.


## Describe alternatives you've considered

Do nothing
posthog/settings/web.py
if url.endswith("/recorder.js") and not DEBUG:
        headers["Cache-Control"] = "max-age=31536000, public"
WHITENOISE_ADD_HEADERS_FUNCTION = add_recorder_js_headers
CSRF_COOKIE_NAME = "posthog_csrftoken"
GZIP_RESPONSE_ALLOW_LIST = get_list(
    os.getenv(
        "GZIP_RESPONSE_ALLOW_LIST",
        ",".join(
            [
                "^/?api/projects/\\d+/session_recordings/.*/snapshots/?$",
                "^/?api/plugin_config/\\d+/frontend/?$",
                "^/?api/projects/@current/property_definitions/?$",
                "^/?api/projects/\\d+/event_definitions/?$",
                "^/?api/projects/\\d+/insights/(trend|funnel)/?$",
                "^/?api/projects/\\d+/insights/\\d+/?$",
                "^/?api/projects/\\d+/dashboards/\\d+/?$",
                "^/?api/projects/\\d+/actions/?$",
                "^/?api/projects/\\d+/session_recordings/?$",
                "^/?api/projects/\\d+/exports/\\d+/content/?$",
                "^/?api/projects/\\d+/activity_log/important_changes/?$",
                "^/?api/projects/\\d+/uploaded_media/?$",
                "^/uploaded_media/.*$",
                "^/year_in_posthog/.*$",
            ]
        ),
    )
)
KAFKA_PRODUCE_ACK_TIMEOUT_SECONDS = int(os.getenv("KAFKA_PRODUCE_ACK_TIMEOUT_SECONDS", None) or 10)