$ git clone -n https://src.fedoraproject.org/rpms/appstream-data.git /var/lib/mock/f39-build-2249725-54005/root/chroot_tmpdir/scmroot/appstream-data
Cloning into '/var/lib/mock/f39-build-2249725-54005/root/chroot_tmpdir/scmroot/appstream-data'...
$ git fetch origin 8072fb917d7495e052ad4413b7671b527e47e606:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/appstream-data
 * [new ref]         8072fb917d7495e052ad4413b7671b527e47e606 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8072fb9 New metadata version