Add Android 11 feautures support, extend firebase test devices

[azaat]

• Update app to support scoped storage

[azaat]

Scoped storage requires us to have video, image, and document files all in their own directories - which is not very convenient when we want to save videos, images and meta csv files in one directory and easily collect them

Summary:

• The solution with saving everything as regular files to Documents works only partially and breaks last media scanner logic
• Legacy storage access can be requested on both Android 10 and 11, but only when the app targets API <=29. So when we change to API 30, this won't work
• Duplicating media files - too much memory

[azaat]

@anastasiia-kornilova
Is there anything else I might've missed?