## Bug description

When calculating Trends results with an aggregated (e.g. single output, like big number) display type, WAU/MAU don't work. This is because we have an `ACTIVE_USERS_SQL` query for time series display types, but we don't have a version of this for aggregated display types. (See ZEN-1043.)

## How to reproduce

1. Create an insight with a single WAU or MAU series.
2. Switch display type to "Number".
3. Open the "Debug ClickHouse queries" modal from the command palette.
4. See `COUNT(*)` instead of `COUNT(DISTINCT person_id)`.

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

posthog/queries/trends/trends_event_query.py
EventQuery._determine_should_join_persons(self)
        if self._using_person_on_events:
            self._should_join_distinct_ids = False
            self._should_join_persons = False
    def _get_extra_person_columns(self) -> str:
        if self._using_person_on_events:
            return " ".join(
                ", {extract} as {column_name}".format(
                    extract=get_property_string_expr(
                        "events",
                        column_name,
                        var=f"'{column_name}'",
                        allow_denormalized_props=False,
                        column="person_properties",
                        table_alias=self.EVENT_TABLE_ALIAS,
                        materialised_table_column="person_properties",
                    ),
                    column_name=column_name,
                )
                for column_name in self._extra_person_fields
            )
        else:
            return " ".join(
                f", {self.PERSON_TABLE_ALIAS}.{column_name} as {column_name}"
                for column_name in self._extra_person_fields
            )
    def _determine_should_join_distinct_ids(self) -> None: