$ git clone -n https://src.fedoraproject.org/rpms/rcs.git /var/lib/mock/f45-build-34370-685/root/chroot_tmpdir/scmroot/rcs
Cloning into '/var/lib/mock/f45-build-34370-685/root/chroot_tmpdir/scmroot/rcs'...
$ git fetch origin 698885da2c616f45d61fad3bc85113cb96965fb3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rcs
 * [new ref]         698885da2c616f45d61fad3bc85113cb96965fb3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 698885d Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild