## Bug description

When I create a fairly simple query (event + 1 filter) and click on the graph to open the person models (sep 3), I get 25 people, whereas the graph says there should be 17 ([see this internal link](https://app.posthog.com/insights?insight=TRENDS&interval=day&display=ActionsLineGraph&events=%5B%7B%22id%22%3A%22insight%20loaded%22%2C%22name%22%3A%22insight%20loaded%22%2C%22type%22%3A%22events%22%2C%22order%22%3A0%2C%22math%22%3A%22dau%22%7D%5D&filter_test_accounts=true&actions=%5B%5D&new_entity=%5B%5D&breakdown=false&breakdown_type&properties=%5B%7B%22key%22%3A%22insight%22%2C%22value%22%3A%5B%22STICKINESS%22%5D%2C%22operator%22%3A%22exact%22%2C%22type%22%3A%22event%22%7D%5D&date_from=2021-08-30&date_to=2021-09-06#personModal=%7B%22action%22%3A%7B%22id%22%3A%22insight%20loaded%22%2C%22type%22%3A%22events%22%2C%22order%22%3A0%2C%22name%22%3A%22insight%20loaded%22%2C%22math%22%3A%22dau%22%2C%22math_property%22%3Anull%2C%22properties%22%3A%5B%5D%7D%2C%22label%22%3A%22insight%20loaded%22%2C%22date_from%22%3A%222021-09-03%22%2C%22date_to%22%3A%222021-09-03%22%2C%22filters%22%3A%7B%22insight%22%3A%22TRENDS%22%2C%22interval%22%3A%22day%22%2C%22display%22%3A%22ActionsLineGraph%22%2C%22events%22%3A%5B%7B%22id%22%3A%22insight%20loaded%22%2C%22name%22%3A%22insight%20loaded%22%2C%22type%22%3A%22events%22%2C%22order%22%3A0%2C%22math%22%3A%22dau%22%7D%5D%2C%22filter_test_accounts%22%3Atrue%2C%22actions%22%3A%5B%5D%2C%22new_entity%22%3A%5B%5D%2C%22breakdown%22%3Afalse%2C%22breakdown_type%22%3Anull%2C%22properties%22%3A%5B%7B%22key%22%3A%22insight%22%2C%22value%22%3A%5B%22STICKINESS%22%5D%2C%22operator%22%3A%22exact%22%2C%22type%22%3A%22event%22%7D%5D%2C%22date_from%22%3A%222021-08-30%22%2C%22date_to%22%3A%222021-09-06%22%7D%2C%22saveOriginal%22%3Atrue%7D))

The same thing happens with a [breakdown query](https://app.posthog.com/insights?insight=TRENDS&interval=day&display=ActionsLineGraph&events=%5B%7B%22id%22%3A%22insight%20loaded%22%2C%22name%22%3A%22insight%20loaded%22%2C%22type%22%3A%22events%22%2C%22order%22%3A0%2C%22math%22%3A%22dau%22%7D%5D&filter_test_accounts=true&properties=%5B%5D&actions=%5B%5D&new_entity=%5B%5D&breakdown=insight&breakdown_type=event)

## Expected behavior

The person modal should have 17 people

## How to reproduce

1. Go to link above
2. Click on sep 3
3. Verify there are 25 people

## Environment

- [ ] PostHog Cloud
- [ ] self-hosted PostHog, version/commit: _please provide_

## Additional context

Looks like when passing through the date as 3rd of september, the query looks like this, which is probably where the 25 comes from (3rd + 4th of sept combined):
![image](https://user-images.githubusercontent.com/1727427/132249205-22c77f31-aee8-4d6a-819f-eafecd02ad46.png)


cc @EDsCODE @macobo 


#### *Thank you* for your bug report – we love squashing them!

posthog/api/test/test_action_people.py
"date_to": "2020-01-07",
                    "display": TRENDS_CUMULATIVE,  
                    ENTITY_TYPE: "events",
                    ENTITY_ID: "watched movie",
                    "breakdown_type": "cohort",
                    "breakdown_value": "all",
                    "breakdown": [cohort.pk],
                },
            ).json()
            self.assertEqual(len(people["results"][0]["people"]), 4)
            ordered_people = sorted(people["results"][0]["people"], key=lambda i: i["id"])
            self.assertEqual(ordered_people[0]["id"], person1.pk)
        def test_breakdown_by_person_property_people_endpoint(self):
            person1, person2, person3, person4 = self._create_multiple_people()
            action = action_factory(name="watched movie", team=self.team)
            people = self.client.get(
                "/api/action/people/",
                data={
                    "date_from": "2020-01-01",
                    "date_to": "2020-01-07",
                    ENTITY_TYPE: "events",
                    ENTITY_ID: "watched movie",
                    "breakdown_type": "person",
                    "breakdown_value": "person3",
                    "breakdown": "name",
                },
            ).json()
            self.assertEqual(len(people["results"][0]["people"]), 1)
            self.assertEqual(people["results"][0]["people"][0]["id"], person3.pk)
        def test_breakdown_by_event_property_people_endpoint(self):