Add findBy* async polling queries from @testing-library/dom

[alexkrolick]

It would be pretty handy if pptr-testing-libary supported https://github.com/alexkrolick/dom-testing-addon-async

Basically, it adds Cypress-like functionality to queries by automatically retrying them until a timeout, and is async by default

[patrickhulce]

Ah interesting so it wraps everything in waitFor automatically? I'm not opposed to it but wouldn't want to greatly complicate the integration and update story. As you can tell, I'm not actively adding/upkeeping functions I'm not using myself :)

[MynockSpit]

Am I right in thinking that this (findBy* and findAllBy*) is now part of DTL core? The docs seem to imply that.

[patrickhulce]

They are part of dom-testing-library core now, so we should be able to handle this better within pptr-testing-library now 👍