GitLab

Based on Buster-slim

- clients/python/duniterpy#118
- To speed-up the jobs

[mod] clients/python/silkaj#286: Install Black from pip instead of the Debian packages

- This in order to get last version which behaves differently

- clients/python/silkaj/issues/249

This reverts commit 5f4a5b18.

- https://github.com/sdispater/poetry/issues/1500
- fix clikit version otherwise the runtime is broken

- get apt lists and remove them in order to slim down the image

- as cffi dependency needs to be compiled
- Could be removed later when fixed upstream (cffi, poetry)
- In order to lighten the image and to speed-up the job

- based on Debian Buster slim
- build jobs inherits from common block: publish with tag and latestt
- Install libsodium
- Install Poetry with pip
- 3.8: install Black