Documentation to support post devcontainer build requirements

[braibaud]

I have added the steps required (once the devcontainer has been built) in order to allow pre-commit workflow to run. Side note: I have a feeling all these steps could well be integrated while building the container, but this goes beyond my expertise.

[oncleben31]

Thank you for the contribution to the documentation. You are right the installation of linting requirements is not obvious. I like the the idea to document it but I would like to make it simple to avoid too much terminal command for the users.

Perfect solution could be to integrate this requirement installation in the container or having a one command to install the requirement in an isolated environment usable in local or in the container.

Without touching the code you approach is good. What do you think about reusing the command from the CI as a starting point ?

pip install --constraint=.github/workflows/constraints.txt pre-commit black flake8 reorder-python-imports

It allows to install all required tool with pinned version.