$ git clone -n https://src.fedoraproject.org/rpms/rpmdevtools.git /var/lib/mock/f45-build-34660-690/root/chroot_tmpdir/scmroot/rpmdevtools
Cloning into '/var/lib/mock/f45-build-34660-690/root/chroot_tmpdir/scmroot/rpmdevtools'...
$ git fetch origin 4926e145b7c4d9b425c6661031e8f9242080b0f1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rpmdevtools
 * [new ref]         4926e145b7c4d9b425c6661031e8f9242080b0f1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4926e14 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild