Cross-Library: support Google's Compose Preview Screenshot Testing Tool

[sergio-sastre]

The idea is that one can generate screenshot tests automatically from the previews, and run them with the Screenshot test library of his choice!

For that, one can use a solution similar to the one described in the blog post automate-screenshot-testing-for-compose-previews-via-reflection together with the capability of AndroidUiTestingUtils of writing Cross-Library screenshot tests

Moreover, it'd be good to wait till Google releases its own solution to see how this solution would complement it, e.g.

• run auto-generated tests from previews together with other existing screenshot tests
• this would also allow you to run screenshot tests on devices
• use library specific features, like "screenshot tests for accessibility"

On the other hand, it might also have some limitations, e.g. not all libraries might support everything the previews can.