Make Example app run on web

[j-piasecki]

Description

This PR makes changes necessary to make Example app run on web:

• adds react-native-web as a dependency
• modifies web-specific babel config to be more in line with the default one and maps react-native to react-native-web
• removes the underscore from 60_000 in the Camera example as it was causing errors on web (and some older iPhones IIRC)

Test plan

Checked if any of the test cases crashes (those that use Gesture.Exclusive do, but they should be fixed by #2058, and Manual Gestures example crashes as Gesture.Manual is not implemented on web).