Add Maestro screenshot generation

[TheLastProject]

This is a PoC of generation screenshots with Maestro.

TODO:

• Use "Catima" instead of "Catima Debug" app name (use the release APK perhaps?)
• Generate all 7 other screenshots (TODO: requires dark mode, figure out how)
• Somehow activate Android demo mode for prettier screenshots (this ensures the screenshots don't show a random timestamp in the title bar)
• Somehow use different locales
• Document this or write a script to generate all screenshots

One very big downside of Maestro is that it's slow. Extremely slow. It takes a full 6 minutes to generate this one screenshots. Scaling this to all Catima's supported languages may not be reasonable.

You can try the current code as follows:

1. Install Maestro (sadly they don't have properly Linux packages)
2. Manually start an Android Studio emulator (the autostart is broken on Linux: Unsupported architecture UNKNOWN [1.33.0] mobile-dev-inc/Maestro#1492)
3. Run maestro test maestro/01.yaml
4. Wait 6(!) minutes
5. Look at the new screenshot-01 image that's generated

[TheLastProject]

Because Maestro is so slow we should see about using something else instead. Sure, Maestro is easiest, but it's ridiculously slow.