Para 15.6 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/home:jjacque/15.6/home:jjacque.repo
zypper refresh
zypper install perl-Net-DNS-Resolver-Mock
Para 15.5 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/home:jjacque/15.5/home:jjacque.repo
zypper refresh
zypper install perl-Net-DNS-Resolver-Mock
Para 15.4 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/home:jjacque/15.4/home:jjacque.repo
zypper refresh
zypper install perl-Net-DNS-Resolver-Mock