## Is your feature request related to a problem?

There's only 2 files where we use pandas, but pandas is 49MB and numpy is another 86MB, slowing down builds massively.

## Describe the solution you'd like

Replace pandas with a pure SQL/Python solution in
- posthog/queries/trends.py
- posthog/queries/sessions.py

Both of those have equivalent examples in Clickhouse (ee/clickhouse) that don't use Pandas.

## Describe alternatives you've considered

Continue using Pandas and clogging builds

## Additional context



#### *Thank you* for your feature request – we love each and every one!

posthog/queries/test/test_trends.py
self._create_multiple_people()
            with freeze_time("2020-01-04T13:01:01Z"):
                event_response = trends().run(
                    Filter(
                        data={
                            "date_from": "-14d",
                            "breakdown": "name",
                            "breakdown_type": "person",
                            "display": "ActionsPie",
                            "events": [
                                {
                                    "id": "watched movie",
                                    "name": "watched movie",
                                    "type": "events",
                                    "order": 0,
                                    "math": "dau",
                                }
                            ],
                        }
                    ),
                    self.team,
                )
                self.assertDictContainsSubset({"breakdown_value": "person1", "aggregated_value": 1}, event_response[0])
                self.assertDictContainsSubset({"breakdown_value": "person2", "aggregated_value": 1}, event_response[1])
                self.assertDictContainsSubset({"breakdown_value": "person3", "aggregated_value": 1}, event_response[2])
        def test_lifecycle_trend(self):