## 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.


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posthog/test/test_event_model.py
action_sign_up = Action.objects.create(team=self.team, name="signed up")
        ActionStep.objects.create(
            action=action_sign_up, tag_name="button", text="Sign up!", event="$autocapture",
        )
        
        ActionStep.objects.create(
            action=action_sign_up, tag_name="button", text="Sign up!", event="$autocapture",
        )
        action_credit_card = Action.objects.create(team=self.team, name="paid")
        ActionStep.objects.create(
            action=action_credit_card, tag_name="button", text="Pay $10", event="$autocapture",
        )
        
        person_stopped_after_signup = Person.objects.create(distinct_ids=["stopped_after_signup"], team=self.team)
        event_sign_up_1 = self._signup_event("stopped_after_signup")
        self.assertEqual(event_sign_up_1.actions, [action_sign_up])
    def test_selector(self):
        action_watch_movie = Action.objects.create(team=self.team, name="watch movie")
        ActionStep.objects.create(
            action=action_watch_movie, text="Watch now", selector="div > a.watch_movie", event="$autocapture",
        )
        Person.objects.create(distinct_ids=["watched_movie"], team=self.team)
        event = self._movie_event("watched_movie")
        self.assertEqual(event.actions, [action_watch_movie])
    def test_attributes(self):