Add inital CI workflow (#12)

* Add inital CI workflow

* Run unit tests

* Run integration tests & ktlint

* Split job, set REPO_ROOT

* Update to satisfy new cargo clippy

* Upload an artifact

* Run runtime tests in CI

* Add missing test.sh

* Make script path indepdendent

* Run clippy on Rust runtime

* move artifact upload to the correct job

* Don't upload target

* Fix Rust code formatting

* Fix kotlin codestyle

* Fix merge issue