[CI] Add basic Argent end-to-end tests (#4318)

## Description

Extends `android` and `ios` workflows with an e2e step, which uses the
prepared artifact to run the Argent flows on the Expo example app.

The flow execution is screen-recorded on both platforms to make
identifying issues easier. In case the workflow fails, the recording
will be stored as an artifact.

## Test plan

Status checks