## Bug description

Creating a selector with an attribute isn't working at all.

`[data-attr="bla"]`

## Expected behavior

It should work

## How to reproduce

1. Create action
2. Add an attribute in the selector
3. 


## Additional context

The reason for this is that we store the attributes as `attr__data-attr` but we do not add `attr__` in the filtering. I am working on a solution.


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

posthog/models/event.py
events = self.filter(action=action).add_person_id(team_id=action.team_id)
        if order_by:
            events = events.order_by(order_by)
        return events
    def filter_by_event_with_people(self, event, team_id, order_by="-id") -> models.QuerySet:
        events = self.filter(team_id=team_id).filter(event=event).add_person_id(team_id=team_id)
        if order_by:
            events = events.order_by(order_by)
        return events
    def query_retention(self, filters, team, start_entity: Optional[Entity] = None) -> dict:
        events: QuerySet = QuerySet()
        entity = Entity({"id": "$pageview", "type": TREND_FILTER_TYPE_EVENTS}) if not start_entity else start_entity
        if entity.type == TREND_FILTER_TYPE_EVENTS:
            events = Event.objects.filter_by_event_with_people(event=entity.id, team_id=team.id)