AUT-Setup CI

[superus8r]

Setup GitHub Actions to achieve the following:

• Running unit tests
• Running instrumented tests
• Running Gradle lint

Also, setup Fastlane to automate app distribution through Firebase.
Right now, Fastlane only runs the unit tests which is only overhead. I understand that!
However, the step is ready to use other Fastlane commands (e.g. firebase_app_distribution).

run-ui-tests job uses a macOS environment
why macOS?

• To prevent using Firebase TestLab, and avoid build quotas in an open-source project.
• The macOS environment on Github Actions support HAXM