$ git clone -n https://src.fedoraproject.org/rpms/shotwell.git /var/lib/mock/f40-build-788341-135103/root/chroot_tmpdir/scmroot/shotwell
Cloning into '/var/lib/mock/f40-build-788341-135103/root/chroot_tmpdir/scmroot/shotwell'...
$ git fetch origin 5f57b500f5aec4c960835b268965f40707c72675:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/shotwell
 * [new ref]         5f57b500f5aec4c960835b268965f40707c72675 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5f57b50 Update to 0.32.6