$ git clone -n https://src.fedoraproject.org/rpms/rubygem-net-sftp.git /var/lib/mock/f45-build-35113-693/root/chroot_tmpdir/scmroot/rubygem-net-sftp
Cloning into '/var/lib/mock/f45-build-35113-693/root/chroot_tmpdir/scmroot/rubygem-net-sftp'...
$ git fetch origin 87deb6e9438324efdd59585408a501964eda16d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-net-sftp
 * [new ref]         87deb6e9438324efdd59585408a501964eda16d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 87deb6e Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild