[Feature] add details to setup python envs and unit test workflow

[mxochicale]

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Currently there is no contribution guideline nor python env to do dev work

[mxochicale]

ERROR using new uv env

pip install -e .
Defaulting to user installation because normal site-packages is not writeable
Looking in indexes: https://pypi.org/simple, https://pypi.ngc.nvidia.com
Obtaining file:///home/mxochicale/Desktop/ucl/brainGlobe/repositories/brainglobe-atlasapi
  Installing build dependencies ... done
  Checking if build backend supports build_editable ... done
ERROR: Project file:///home/mxochicale/Desktop/ucl/brainGlobe/repositories/brainglobe-atlasapi has a 'pyproject.toml' and its build backend is missing the 'build_editable' hook. Since it does not have a 'setup.py' nor a 'setup.cfg', it cannot be installed in editable mode. Consider using a build backend that supports PEP 660.

[stellaprins]

This may have to do with the setuptools version (currently the requirements are set to <45).

See this comment on StackOverflow:

Note: To be able to do an editable installation to your user site (pip install -e --user), you need a system installed setuptools v62.0.0 or newer.

[adamltyson]

The requirements are set to setuptools>=45, this seems to work fine with pip on my system (in a conda env).