ElementInternals ARIA role conflict resolution

When resolving the role of an element with an attached internals role, and the element defines an explicit none role and is either focusable or has a global ARIA attribute, axe-core currently resolves the internal role as the implicit role.

```html
btn none focusable

customElements.define(
'my-button',
class MyButton extends HTMLElement {
constructor() {
super();
this._internals = this.attachInternals();
this._internals.role = 'button';
}
}
)

```

According to the spec this should be correct, however no browser currently supports this. Tracking here so we can watch it. Filed bugs with:

- [ ] [Chrome](https://issues.chromium.org/issues/522529333)
- [ ] [Firefox](https://bugzilla.mozilla.org/show_bug.cgi?id=2046886)
- [ ] [Safari](https://bugs.webkit.org/show_bug.cgi?id=316919)
- [ ] [WPT](https://github.com/web-platform-tests/wpt/issues/60563)

Start by reviewing the ElementInternals and ARIA role conflict described in this issue, then check the linked Chrome, Firefox, Safari, and WPT bugs for current implementation status. No axe-core file or test is identified; done would require a clearly defined project change after browser or specification support advances.

Written by the indexing model from the issue text.