$ git clone -n https://src.fedoraproject.org/rpms/cleanfeed.git /var/lib/mock/f45-build-6752-350/root/chroot_tmpdir/scmroot/cleanfeed
Cloning into '/var/lib/mock/f45-build-6752-350/root/chroot_tmpdir/scmroot/cleanfeed'...
$ git fetch origin bc4c88b130b221c908507d8dd01d6c8d1b479137:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/cleanfeed
 * [new ref]         bc4c88b130b221c908507d8dd01d6c8d1b479137 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bc4c88b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild