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/api/test/test_person.py
Person.objects.create(
            team=self.team, properties={"random_prop": "asdf", "some other prop": "with some text"},
        )
        Person.objects.create(team=self.team, properties={"random_prop": "asdf"})
        Person.objects.create(team=self.team, properties={"random_prop": "qwerty"})
        Person.objects.create(team=self.team, properties={"something_else": "qwerty"})
        response = self.client.get("/api/person/values/?key=random_prop")
        self.assertEqual(response.status_code, status.HTTP_200_OK)
        response_data = response.json()
        self.assertEqual(response_data[0]["name"], "asdf")
        self.assertEqual(response_data[0]["count"], 2)
        self.assertEqual(response_data[1]["name"], "qwerty")
        self.assertEqual(response_data[1]["count"], 1)
        self.assertEqual(len(response_data), 2)
        response = self.client.get("/api/person/values/?key=random_prop&value=qw")
        self.assertEqual(response.status_code, status.HTTP_200_OK)
        self.assertEqual(response.json()[0]["name"], "qwerty")
        self.assertEqual(response.json()[0]["count"], 1)
    def test_filter_by_cohort(self):