refactor: unify tests in test apps

[alduzy]

Description

This PR intents to unify tests used by test apps

Changes

• moved tests to common directory
• removed duplicates

Test code and steps to reproduce

Checklist

• Included code example that can be used to test this change
• Updated TS types
• Updated documentation:
  • https://github.com/software-mansion/react-native-screens/blob/main/guides/GUIDE_FOR_LIBRARY_AUTHORS.md
  • https://github.com/software-mansion/react-native-screens/blob/main/native-stack/README.md
  • https://github.com/software-mansion/react-native-screens/blob/main/src/types.tsx
  • https://github.com/software-mansion/react-native-screens/blob/main/src/native-stack/types.tsx
• Ensured that CI passes

[kkafar]

Good job overall. Left important remark

[kkafar]

Oh, and there is one more thing. There could be some test cases that were present only in FabricTestExample and not in TestsExample or the other way around. Please make sure, that we do not remove them entirely.

[kkafar]

Yeah, it looks nice now 🎉

At last we need better name for the tests directory, as this is usually used in context of unit/integration tests and gives wrong clues about its contents. What do you think of test-screens or something similar?

[kkafar]

I think we're good to go 🟢
If you tested & everything is working I think we can proceed.