* feat: adds s3 object storage configuration
* feat: adds s3 integration test
* chore: use map
* fix: forgot license header
* fix: checking if bucket is empty in test_on
* chore: address CR issues
* refactor: run s3 test with dotenv
* chore: randomize grpc port for test
* fix: README in tests-integration
* chore: remove redundant comments
