TST: CI instability (setuptools + munch)

[neutrinoceros]

CI is currently unstable because (see https://github.com/SAIL-Labs/AMICAL/actions/runs/4180212707)
What happens is that the newest version of setuptools (namely 67.3), which provides pkg_resources, deprecates pkg_resources.declare_namespece (see pypa/setuptools#3434), which is used by munch.

This has been a problem with munch for a while already (see Infinidat/munch#67), and it's actually been solved on the dev branch for 3 years, but the patch was never released, and now the repo looks essentially unmaintained.

I would advocate that we should try to get rid of munch as a dependency, though I may not be fully aware of what challenges this poses. TBD with @DrSoulain

[DrSoulain]

Indeed, munch seems to be too unstable to be used. It is only used to transform dictionary into class-like object to be easily accessible. We should be able to write a built-in dedicated function to do so.

[vandalt]

In the past, I used Box for a similar purpose. It seems still well maintained: https://github.com/cdgriffith/Box.

[vandalt]

Oops I just realized this had been closed already. Will leave the comment in case it can help someone in the future.

[neutrinoceros]

Good to know ! If we ever want to stop vendoring munch, this seems like a decent option