Rework Dockerfile: Optimisations, embed sources, Introduce CI/CD, publish image on Registry
Switch to slim Python image to reduce the image size, and get latest OS and Python version Install g++ not available on the slim image, required by plyvel
Clean APT cache to reduce image size
use apt, remove unnecessary noninteractive
Copy py-g1-migrator sources inside the image Create empty input and output directories, in order not copy huge data which could exist in local development