versioningit replaces the need for (and will overwrite) the version keyword
to the setup() function, so you should remove any such keyword from your
setup.py/setup.cfg to reduce confusion.

[tool.versioningit.format]

# Format used when there have been commits since the most recent tag:
distance = "{base_version}.post{distance}+{vcs}{rev}"

# Format used when there are uncommitted changes:
dirty = "{base_version}+d{build_date:%Y%m%d}"

# Format used when there are both commits and uncommitted changes:
distance-dirty = "{base_version}.post{distance}+{vcs}{rev}.d{build_date:%Y%m%d}"