For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:tools:scm/openSUSE_Tumbleweed/devel:tools:scm.repo
zypper refresh
zypper install gitea
For 16.0 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:tools:scm/16.0/devel:tools:scm.repo
zypper refresh
zypper install gitea
For 15.7 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:tools:scm/15.7/devel:tools:scm.repo
zypper refresh
zypper install gitea