$ git clone -n https://src.fedoraproject.org/rpms/libgexiv2.git /var/lib/mock/f45-build-16280-484/root/chroot_tmpdir/scmroot/libgexiv2
Cloning into '/var/lib/mock/f45-build-16280-484/root/chroot_tmpdir/scmroot/libgexiv2'...
$ git fetch origin d8a483817e21d036bb4b623eb8f1d520f37cc8aa:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libgexiv2
 * [new ref]         d8a483817e21d036bb4b623eb8f1d520f37cc8aa -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d8a4838 Update to 0.16.2