## Bug description

Trying to look at insights for feature flags no longer works (see screenshot below).

<img width="1329" alt="" src="https://user-images.githubusercontent.com/5864173/100642031-de24cb00-32fd-11eb-88b4-047c4f82124f.png">


Removing the breakdown works but then you can't see the difference between the binary values.

![image](https://user-images.githubusercontent.com/5864173/100642046-e2e97f00-32fd-11eb-8ae5-4238f899c8b8.png)


## Expected behavior

Insights should be shown as before.


## How to reproduce

1. Click on the insights link on any feature flag row.

## Environment

Cloud (Clickhouse).

## Additional context



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

ee/clickhouse/queries/trends/breakdown.py
element_params = {"key": filter.breakdown, "limit": 20, "team_id": team_id}
        try:
            top_elements_array_result = sync_execute(query, element_params)
            top_elements_array = top_elements_array_result[0][0]
        except:
            top_elements_array = []
        return top_elements_array
    def _format_breakdown_cohort_join_query(self, breakdown: List[Any], team_id: int) -> Tuple[str, List, Dict]:
        cohorts = Cohort.objects.filter(team_id=team_id, pk__in=[b for b in breakdown if b != "all"])
        cohort_queries, params = self._parse_breakdown_cohorts(cohorts)
        ids = [cohort.pk for cohort in cohorts]
        return cohort_queries, ids, params
    def _parse_breakdown_cohorts(self, cohorts: BaseManager) -> Tuple[str, Dict]:
        queries = []
        params: Dict[str, Any] = {}
        for cohort in cohorts:
            person_id_query, cohort_filter_params = format_filter_query(cohort)
            params = {**params, **cohort_filter_params}
            cohort_query = person_id_query.replace(
                "SELECT distinct_id", "SELECT distinct_id, {} as value".format(cohort.pk)
            )
            queries.append(cohort_query)
        return " UNION ALL ".join(queries), params