loongson/pypi: links for button

loongson/mirror button-0.0.3.post3.tar.gz
loongson/mirror button-0.0.3.post2.tar.gz
loongson/mirror button-0.0.3.tar.gz
loongson/mirror button-0.0.1.tar.gz
loongson/mirror button-0.0.1-py3.7.egg