$ git clone -n https://src.fedoraproject.org/rpms/mirrorlist-server.git /var/lib/mock/f45-build-39716-750/root/chroot_tmpdir/scmroot/mirrorlist-server
Cloning into '/var/lib/mock/f45-build-39716-750/root/chroot_tmpdir/scmroot/mirrorlist-server'...
$ git fetch origin 7282a74c9b6d58c73be87990b765a91ce76c9b68:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mirrorlist-server
 * [new ref]         7282a74c9b6d58c73be87990b765a91ce76c9b68 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7282a74 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild