loongson/pypi: links for footprints

loongson/mirror footprints-2.0.0.tar.gz
loongson/mirror footprints-2.0.0-py3-none-any.whl
loongson/mirror footprints-2.0.0b2.tar.gz
loongson/mirror footprints-2.0.0b2-py3-none-any.whl
loongson/mirror footprints-2.0.0b1.tar.gz
loongson/mirror footprints-2.0.0b1-py3-none-any.whl