$ git clone -n https://src.fedoraproject.org/rpms/gpac.git /var/lib/mock/f41-build-850228-165169/root/chroot_tmpdir/scmroot/gpac
Cloning into '/var/lib/mock/f41-build-850228-165169/root/chroot_tmpdir/scmroot/gpac'...
$ git fetch origin cab4f0a0129dc870266f27c08423eca8c334f529:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gpac
 * [new ref]         cab4f0a0129dc870266f27c08423eca8c334f529 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cab4f0a initial import (resolves rhbz#2270199)