## 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
)
SOCIAL_AUTH_STRATEGY = "social_django.strategy.DjangoStrategy"
SOCIAL_AUTH_STORAGE = "social_django.models.DjangoStorage"
SOCIAL_AUTH_FIELDS_STORED_IN_SESSION = ["invite_id", "user_name", "email_opt_in", "organization_name"]
SOCIAL_AUTH_GITHUB_SCOPE = ["user:email"]
SOCIAL_AUTH_GITHUB_KEY = os.getenv("SOCIAL_AUTH_GITHUB_KEY")
SOCIAL_AUTH_GITHUB_SECRET = os.getenv("SOCIAL_AUTH_GITHUB_SECRET")
SOCIAL_AUTH_GITLAB_SCOPE = ["read_user"]
SOCIAL_AUTH_GITLAB_KEY = os.getenv("SOCIAL_AUTH_GITLAB_KEY")
SOCIAL_AUTH_GITLAB_SECRET = os.getenv("SOCIAL_AUTH_GITLAB_SECRET")
SOCIAL_AUTH_GITLAB_API_URL = os.getenv("SOCIAL_AUTH_GITLAB_API_URL", "https://gitlab.com")
AUTH_PASSWORD_VALIDATORS = [{"NAME": "django.contrib.auth.password_validation.MinimumLengthValidator"}]
PASSWORD_RESET_TIMEOUT = 86_400  
LANGUAGE_CODE = "en-us"
TIME_ZONE = "UTC"
USE_I18N = True
USE_L10N = True
USE_TZ = True
STATIC_ROOT = os.path.join(BASE_DIR, "staticfiles")
STATIC_URL = "/static/"
STATICFILES_DIRS = [os.path.join(BASE_DIR, "frontend/dist"), os.path.join(BASE_DIR, "posthog/year_in_posthog/images")]
STATICFILES_STORAGE = "whitenoise.storage.CompressedManifestStaticFilesStorage"
AUTH_USER_MODEL = "posthog.User"
LOGIN_URL = "/login"
LOGOUT_URL = "/logout"
LOGIN_REDIRECT_URL = "/"
APPEND_SLASH = False
CORS_URLS_REGEX = r"^/api/.*$"
REST_FRAMEWORK = {
    "DEFAULT_AUTHENTICATION_CLASSES": [