The attribute-behavior fixture now uses `createRoot().render()` and
`renderToReadableStream` instead of depdrecated APIs.
This revealed some changes to the snapshots that I annotated for
discussion.
I also added some new tests related to upcoming changes for easier
future diffing.
Also adds support for running the attribute-behavior fixture using Apple
Silicon chips (Apple MBP M-series).
* Fix missing key warning
* Add build instructions
* Update interpretation now that React 17 is latest stable and 18 is next
* Ignore ReactDOM.render deprecation warning
* Ensure a server implementation with `renderToString` is used
* Update AttributeTableSnapshot
* Ensure Popover doesn't overflow