$ git clone -n https://src.fedoraproject.org/rpms/lumina-desktop.git /var/lib/mock/f45-build-17729-503/root/chroot_tmpdir/scmroot/lumina-desktop
Cloning into '/var/lib/mock/f45-build-17729-503/root/chroot_tmpdir/scmroot/lumina-desktop'...
$ git fetch origin fefbe71e46d715a53c47bbb55586a57ea4a9e2a9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/lumina-desktop
 * [new ref]         fefbe71e46d715a53c47bbb55586a57ea4a9e2a9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fefbe71 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild