$ git clone -n https://src.fedoraproject.org/rpms/gstreamer1-vaapi.git /var/lib/mock/f38-build-side-42-init-devel-570755-25910/root/chroot_tmpdir/scmroot/gstreamer1-vaapi
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-570755-25910/root/chroot_tmpdir/scmroot/gstreamer1-vaapi'...
$ git fetch origin de17d6f10dfa9b5895f1c3d0a2e60c8b3dca0312:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gstreamer1-vaapi
 * [new ref]         de17d6f10dfa9b5895f1c3d0a2e60c8b3dca0312 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at de17d6f Rebuilt