## 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
ee/models/hook.py
id = models.CharField(primary_key=True, max_length=50, default=generate_random_token)
    user = models.ForeignKey("posthog.User", related_name="rest_hooks", on_delete=models.CASCADE)
    team = models.ForeignKey("posthog.Team", related_name="rest_hooks", on_delete=models.CASCADE)
    resource_id = models.IntegerField(null=True, blank=True)
def find_and_fire_hook(
    event_name: str, instance: models.Model, user_override: Team, payload_override: Optional[dict] = None
):
    if not user_override.organization.is_feature_available(AvailableFeature.ZAPIER):
        return
    hooks = Hook.objects.filter(event=event_name, team=user_override)
    if event_name == "action_performed":
        
        hooks = hooks.filter(models.Q(resource_id=instance.pk))
    for hook in hooks:
        statsd.incr("posthog_cloud_hooks_rest_fired")
        hook.deliver_hook(instance, payload_override)
def deliver_hook_wrapper(target, payload, instance, hook):
    
    DeliverHook.apply_async(kwargs=dict(target=target, payload=payload, hook_id=hook.id))
@receiver(post_save, sender=Hook)
def hook_saved(sender, instance: Hook, created, **kwargs):
    if instance.event == "action_performed":
        get_client().publish(
            "reload-action", json.dumps({"teamId": instance.team_id, "actionId": instance.resource_id})
        )
@mutable_receiver(post_delete, sender=Hook)
def hook_deleted(sender, instance: Hook, **kwargs):
    if instance.event == "action_performed":
        get_client().publish("drop-action", json.dumps({"teamId": instance.team_id, "actionId": instance.resource_id}))