For SLE 15 SP6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Java:packages/SLE_15_SP6/Java:packages.repo
zypper refresh
zypper install boringssl
For SLE 15 SP4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Java:packages/SLE_15_SP4/Java:packages.repo
zypper refresh
zypper install boringssl
For SLE 15 SP2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Java:packages/SLE_15_SP2/Java:packages.repo
zypper refresh
zypper install boringssl