[CI] Upload application artifacts (#4378)

## Description

Updates the CI:
- build-android, build-ios are now reusable workflows that upload the
app binary once finished
  - the apps are now built in release variant
- adds android, ios workflows that build expo example (tests can be
plugged here)
- adds android-basic, ios-basic workflows that build basic example (they
don't depend on the library JS code)

## Test plan

CI run