[bare-expo] Update app.json as for a separate bare-expo project (#6734)
[bare-expo] Update app.json as for a separate bare-expo project (#6734)

# Why

This will let us treat `@[username]/bare-expo` as a proper experience, eg. assign push notifications keys to it.

# How

I used this change to make a configuration change described in https://github.com/expo/expo/pull/6733.

# Test Plan

I don't think this should do any harm. I have used Credentials Manager with `app.json` from this PR (`sdkVersion` wasn't at this time removed) and I achieved what I wanted.
exponent/exponent,exponentjs/exponent,exponent/exponent,exponentjs/exponent,exponentjs/exponent,exponentjs/exponent,exponentjs/exponent,exponentjs/exponent,exponent/exponent,exponent/exponent,exponent/exponent,exponent/exponent,exponentjs/exponent,exponent/exponent,exponentjs/exponent,exponentjs/exponent,exponent/exponent,exponent/exponent