How to configure setuptools with setup.cfg to include platform name, python tag and ABI tag?

Question

Due to the console message of setup.py install is deprecated, I am in the middle of upgrading my existing setup.py install to the recommended setup.cfg with build

My existing setup.py looks something like

from setuptools import setup

setup(
    name='pybindsample',
    version='0.1.0',
    packages=[''],
    package_data={'': ['pybindsample.so']},
    has_ext_modules=lambda: True,
)

My current translation looks like:

setup.cfg

[metadata]
name = pybindsample
version = 0.1.0

[options]
packages = . 

[options.package_data]
. = pybindsample.so

pyproject.toml

[build-system]
requires = ["setuptools"]
build-backend = "setuptools.build_meta"

My question is how can I translate has_ext_modules=lambda: True? has_ext_modules=lambda: True is from the solution here. Without this, after executing python3 -m build --wheel the file name of the generated wheel will become pybindsample-0.1.0-py3-none-any.whl, whereas my old python3 setup.py bdist_wheel will generate wheel with file name pybindsample-0.1.0-cp39-cp39-macosx_11_0_x86_64.whl. I have attempted

setup.cfg

[metadata]
name = pybindsample
version = 0.1.0

[options]
packages = . 
has_ext_modules=lambda: True,

[options.package_data]
. = pybindsample.so

but it still generates pybindsample-0.1.0-py3-none-any.whl, I also attempted

setup.cfg

[metadata]
name = pybindsample
version = 0.1.0

[options]
packages = . 

[options.package_data]
. = pybindsample.so

[bdist_wheel]
python-tag = c39
plat-name = macosx_11_0_x86_64
py-limited-api = c39

this generates pybindsample-0.1.0-cp39-none-macosx_11_0_x86_64.whl, and I couldn't figure out why the abi tag is still none.

What is the right way to configure setuptools with setup.cfg to include platform name, python tag, and ABI tag?