$ git clone -n https://src.fedoraproject.org/rpms/kdesdk-thumbnailers.git /var/lib/mock/f45-build-14685-462/root/chroot_tmpdir/scmroot/kdesdk-thumbnailers
Cloning into '/var/lib/mock/f45-build-14685-462/root/chroot_tmpdir/scmroot/kdesdk-thumbnailers'...
$ git fetch origin 5e592acd05d6486d4e4fcec0a58bb6b914ac9127:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kdesdk-thumbnailers
 * [new ref]         5e592acd05d6486d4e4fcec0a58bb6b914ac9127 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5e592ac 26.08.1