python-calver: update to version 2025.10.20

python-calver: update to version 2025.10.20

Fixes:
 SetuptoolsDeprecationWarning: License classifiers are deprecated.
!!

        ********************************************************************************
        Please consider removing the following classifiers in favor of a SPDX license expression:

        License :: OSI Approved :: Apache Software License

        See https://packaging.python.org/en/latest/guides/writing-pyproject-toml/#license for details.
        ********************************************************************************

!!
  self._finalize_license_expression()

Release notes:
https://github.com/di/calver/releases/tag/2025.10.20

Signed-off-by: Josef Schlehofer <[email protected]>