## 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
selector1 = Selector("div.classone.classtwo > span")
        self.assertEqual(
            selector1.parts[0].__dict__, {"data": {"tag_name": "span"}, "direct_descendant": False, "unique_order": 0,},
        )
        self.assertEqual(
            selector1.parts[1].__dict__,
            {
                "data": {"tag_name": "div", "attr_class__contains": ["classone", "classtwo"],},
                "direct_descendant": True,
                "unique_order": 0,
            },
        )
    def test_nth_child(self):
        selector1 = Selector("div > span:nth-child(3)")
        self.assertEqual(
            selector1.parts[0].__dict__,
            {"data": {"tag_name": "span", "nth_child": "3"}, "direct_descendant": False, "unique_order": 0,},
        )
        self.assertEqual(
            selector1.parts[1].__dict__, {"data": {"tag_name": "div"}, "direct_descendant": True, "unique_order": 0},
        )
    def test_unique_order(self):
        selector1 = Selector("div > div")
        self.assertEqual(
            selector1.parts[0].__dict__, {"data": {"tag_name": "div"}, "direct_descendant": False, "unique_order": 0,},
        )
        self.assertEqual(
            selector1.parts[1].__dict__, {"data": {"tag_name": "div"}, "direct_descendant": True, "unique_order": 1},
        )