For SLE 15 SP7 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:perl/SLE_15_SP7/devel:languages:perl.repo
zypper refresh
zypper install perl-Apache-AuthNetLDAP
For SLE 15 SP6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:perl/SLE_15_SP6/devel:languages:perl.repo
zypper refresh
zypper install perl-Apache-AuthNetLDAP
For SLE 15 SP5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/devel:languages:perl/SLE_15_SP5/devel:languages:perl.repo
zypper refresh
zypper install perl-Apache-AuthNetLDAP