$ git clone -n https://github.com/xcp-ng-rpms/gnutls.git /var/lib/mock/v8.3-u-pcoval1-11086-29514/root/chroot_tmpdir/scmroot/gnutls
Cloning into '/var/lib/mock/v8.3-u-pcoval1-11086-29514/root/chroot_tmpdir/scmroot/gnutls'...
$ git fetch origin 092b0720c568cbc26360110f51ab5e1eee58cdc2:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/gnutls
 * [new ref]         092b0720c568cbc26360110f51ab5e1eee58cdc2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 092b072 bump release for test build