Fight bugs with large unit test coverage and mutation testing in MAUI repo

[akhanalcs]

First of all, I'd like to thank the MAUI team and community working hard at fixing bugs and making it stable.

Getting back to the topic, would the MAUI team be open to these suggestions?

1. Invest in Unit testing and get the test coverage close to 100%.
2. Test the tests using mutation testing library such as Stryker.
3. Invest in Integration testing and UI testing.

I believe automated testing will help MAUI reach stability quickly and also help add new features without inadvertently introducing breaking changes.

Thanks!