libgtk-3-0 from home:MaxxedSUSE:Python-15.6 project

对于 15.6，请以根用户 root 运行下面命令：

zypper addrepo https://download.opensuse.org/repositories/home:MaxxedSUSE:Python-15.6/15.6/home:MaxxedSUSE:Python-15.6.repo
zypper refresh
zypper install libgtk-3-0