$ git clone -n https://src.fedoraproject.org/rpms/gnutls.git /var/lib/mock/f41-build-side-1-2819430-33085/root/chroot_tmpdir/scmroot/gnutls
Cloning into '/var/lib/mock/f41-build-side-1-2819430-33085/root/chroot_tmpdir/scmroot/gnutls'...
$ git fetch origin 8c7b1ef20c13222adb72557169f3d79529c87883:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnutls
 * [new ref]         8c7b1ef20c13222adb72557169f3d79529c87883 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8c7b1ef Update to 3.8.7 upstream release