Add basic test for Modal (#53140)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/53140

As per title, this change adds the boilerplate code for a Fantom test on Modal

## Changelog:
[Internal] -

Reviewed By: andrewdacenko

Differential Revision: D79805808

fbshipit-source-id: c8c77e576a09b346cf29b290d68c75e540d5f146