python-PyYAML from home:louis94_m:freeciv21 project

需要 openSUSE Tumbleweed ，用 root 執行：

zypper addrepo https://download.opensuse.org/repositories/home:louis94_m:freeciv21/openSUSE_Tumbleweed/home:louis94_m:freeciv21.repo
zypper refresh
zypper install python-PyYAML