loongson/pypi: links for s2downloader

loongson/mirror s2downloader-1.4.5.tar.gz
loongson/mirror s2downloader-1.4.3.tar.gz
loongson/mirror s2downloader-1.4.0.tar.gz
loongson/mirror s2downloader-1.3.0.tar.gz
loongson/mirror s2downloader-1.2.3.tar.gz
loongson/mirror s2downloader-1.2.1.tar.gz
loongson/mirror s2downloader-1.2.0.tar.gz