[labs/ssr] Consider other DOM shims for ARIA attr reflection during SSR

### Should this be an RFC?

- [X] This is not a substantial change

### Which package is this a feature request for?

SSR (@lit-labs/ssr)

### Description

Context: https://github.com/lit/lit/pull/3677#discussion_r1142827432

The ARIA attribute reflection logic in `LitElementRenderer` is dependent on our implementation of `attachInternals()` for `HTMLElement` in `@lit-labs/ssr-dom-shim` and may not work for users of other DOM shims. Currently `jsdom` nor `happy-dom` implement `attachInternals()` so there's nothing to support but we'll have to address this as `ElementInternals` gets wider adoption.

### Alternatives and Workarounds

.

Start with LitElementRenderer and the attachInternals() implementation in @lit-labs/ssr-dom-shim. Compare the assumptions there with the DOM behavior exposed by jsdom and happy-dom, then determine what compatibility should look like as ElementInternals support expands. Done should include an agreed approach for ARIA reflection with other DOM shims.

Written by the indexing model from the issue text.