openSUSE 42.3 の場合は、 root で下記のコマンドを実行してください:
zypper addrepo https://download.opensuse.org/repositories/OBS:Server:2.8:Staging/openSUSE_42.3/OBS:Server:2.8:Staging.repo
zypper refresh
zypper install rubygem-minitest-fail-fast
openSUSE 42.2 の場合は、 root で下記のコマンドを実行してください:
zypper addrepo https://download.opensuse.org/repositories/OBS:Server:2.8:Staging/openSUSE_42.2/OBS:Server:2.8:Staging.repo
zypper refresh
zypper install rubygem-minitest-fail-fast
openSUSE 42.1 の場合は、 root で下記のコマンドを実行してください:
zypper addrepo https://download.opensuse.org/repositories/OBS:Server:2.8:Staging/openSUSE_42.1/OBS:Server:2.8:Staging.repo
zypper refresh
zypper install rubygem-minitest-fail-fast