## 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
person_1 = person_factory(team_id=self.team.pk, distinct_ids=["Jane"], properties={"name": "Jane"})
            person_2 = person_factory(team_id=self.team.pk, distinct_ids=["John"], properties={"name": "John"})
            person_3 = person_factory(team_id=self.team.pk, distinct_ids=["Jill"], properties={"name": "Jill"})
            cohort1 = cohort_factory(team=self.team, name="cohort1", groups=[{"properties": {"name": "Jane"}}])
            cohort2 = cohort_factory(team=self.team, name="cohort2", groups=[{"properties": {"name": "John"}}])
            cohort3 = cohort_factory(team=self.team, name="cohort3", groups=[{"properties": {"name": "Jill"}}])
            with freeze_time("2020-01-01 00:06:34"):
                event_factory(
                    team=self.team,
                    event="sign up",
                    distinct_id="John",
                    properties={"$some_property": "value", "$browser": "Chrome"},