Android: CI additions

[souvlakias]

Additions

• Adds the Koin example (Android koin example #6833) to the CI tests, and a relevant doc page so the support of Roboelectric tests can be found in the documentation.
  

  • Note: If we want to avoid another emulator running in CI, we can remove that part and only keep the JVM tests

• Adds a Scheduled Android Tests workflow that will run periodically (every week?), in order to avoid testing certain examples on each merge/PR. (for now this includes only androidtodo)
  Closes Setup a CI workflow that runs on schedule for androidtodo #6845