Checkboxes with `required` attribute don't trigger when unchecking when hx-trigger is at a higher level

I'm not 100% sure if this is a bug or expected behaviour, but it caused enough confusion that I feel I should at least write an issue. The following situation:

```html

Checkbox test

```

```html

It worked!
```

This works fine when you _check_ the box, but not when you _uncheck_ it.

However, it does work if you put the `hx-` attributes directly on the `input`:

```html

Checkbox test

```

If the checkbox is not required, it also works as expected:

```html

Checkbox test

```

It's interesting to note that `onchange` does trigger a change event in JS, but it seems like HTMX does nothing.

Certainly there was a mistake on our side in requiring checkboxes that can be empty, but I also feel HTMX is doing something unexpected here.