We need to migrate python-iso8601 to the pep517 poetry-core
backend as setuptools is not supported when building with a pep517
frontend.
This package currently builds using setuptools as we do not yet
use setuptools with a pep517 build frontend. The package contains
a setuptools fallback which only can be used when using setuptools
without a pep517 frontend as the pep517 frontend will only use the
build backend specified in the package pyproject.toml which is
poetry-core and not setuptools.
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>