Release of #1700. The following lines need to be added to posthog/celery.py to release PR. Deliberately excluded to manually test the PR without sending everyone an email.

```python
# inside setup_periodic_tasks
sender.add_periodic_task(
    crontab(day_of_week="mon"), task_weekly_email_report.s(),
)

# bottom of file
@app.task
def task_weekly_email_report(self):
    from posthog.tasks.email import send_weekly_email_report

    send_weekly_email_report()
```
posthog/celery.py
sender.add_periodic_task(1.0, redis_celery_queue_depth.s(), name="1 sec queue probe", priority=0)
    
    sender.add_periodic_task(10.0, redis_heartbeat.s(), name="10 sec heartbeat", priority=0)
    sender.add_periodic_task(
        crontab(day_of_week="mon,fri"), update_event_partitions.s(),  
    )
    
    if not getattr(settings, "MULTI_TENANCY", False):
        sender.add_periodic_task(crontab(day_of_week="mon"), status_report.s())
    sender.add_periodic_task(15 * 60, calculate_cohort.s(), name="debug")
    sender.add_periodic_task(600, check_cached_items.s(), name="check dashboard items")
    if settings.ASYNC_EVENT_ACTION_MAPPING:
        sender.add_periodic_task(
            (60 * ACTION_EVENT_MAPPING_INTERVAL_MINUTES),
            calculate_event_action_mappings.s(),
            name="calculate event action mappings",
            expires=(60 * ACTION_EVENT_MAPPING_INTERVAL_MINUTES),
        )
@app.task
def redis_heartbeat():