$ git clone -n https://src.fedoraproject.org/rpms/sha.git /var/lib/mock/f45-build-35853-699/root/chroot_tmpdir/scmroot/sha
Cloning into '/var/lib/mock/f45-build-35853-699/root/chroot_tmpdir/scmroot/sha'...
$ git fetch origin 678df6b9ac3d98b0b4ff1a4f236e3daaf72a215a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/sha
 * [new ref]         678df6b9ac3d98b0b4ff1a4f236e3daaf72a215a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 678df6b Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild