Temporarily switch to hatchling backend

[cthoyt]

Closes #147

Temporarily switches to hatch as a backend until astral-sh/uv#10091 is addressed. setuptools still has a major bug with metadata upload to PyPI related to licenses between metadata version 2.3 and 2.4, so it doesn't make sense to go back to that at all.

The following should now work:

$ git clone https://github.com/biopragmatics/curies
$ cd curies
$ git checkout -b hatch-backend
$ python -m pip install -e .[flask,rdflib]
$ python -m curies mapper --host 0.0.0.0 --port 8764 bioregistry

# then, navigate to http://0.0.0.0:8764/sparql