Utiliser circle city to check the validity of the config file

We can even create a git hook...

https://circleci.com/blog/circleci-hacks-validate-circleci-config-on-every-commit-with-a-git-hook/?utm_content=buffer788b4&utm_medium=SCC&utm_source=Twitter&utm_campaign=Twitter-Buffer-Csy

Start by reviewing the CircleCI configuration and any existing Git hook setup, then read the linked CircleCI article for the intended validation workflow. Done means the repository's configuration is checked automatically before a commit, with the expected failure behavior documented or demonstrated.

Written by the indexing model from the issue text.