BLD: use pyproject.toml not setup.py

While at it, remove versioneer and use setuptools_scm
for computing the version dynamically.
This change is mainly because I did not manage to make
versioneer work with pyproject.toml, while setuptools_scm
"just worked" (well, nearly).

Author: ev-br

.gitignore

@@ -26,6 +26,9 @@ share/python-wheels/
 *.egg
 MANIFEST
 
+*_version.py
+
+
 # PyInstaller
 #  Usually these files are written by a python script from a template
 #  before PyInstaller builds the exe, so as to inject date/other infos into it.

array_api_strict/__init__.py

@@ -328,7 +328,7 @@
 __all__ += ['set_array_api_strict_flags', 'get_array_api_strict_flags', 'reset_array_api_strict_flags', 'ArrayAPIStrictFlags']
 
 from . import _version
-__version__ = _version.get_versions()['version']
+__version__ = _version.__version__
 del _version