yast2-vpn from YaST:SLE-15:SP6 project

需要 openSUSE Leap 15.6 ，用 root 執行：

zypper addrepo https://download.opensuse.org/repositories/YaST:SLE-15:SP6/openSUSE_Leap_15.6/YaST:SLE-15:SP6.repo
zypper refresh
zypper install yast2-vpn