loongson/pypi: links for bookshelf-producer

loongson/mirror bookshelf_producer-0.4.0.tar.gz
loongson/mirror bookshelf_producer-0.4.0-py3-none-any.whl
loongson/mirror bookshelf_producer-0.3.1b4.tar.gz
loongson/mirror bookshelf_producer-0.3.1b4-py3-none-any.whl
loongson/mirror bookshelf_producer-0.3.1b3.tar.gz
loongson/mirror bookshelf_producer-0.3.1b3-py3-none-any.whl