$ git clone -n https://github.com/xcp-ng-rpms/gnutls.git /var/lib/mock/v8.3-u-pcoval2-10152-28745/root/chroot_tmpdir/scmroot/gnutls
Cloning into '/var/lib/mock/v8.3-u-pcoval2-10152-28745/root/chroot_tmpdir/scmroot/gnutls'...
$ git fetch origin 21532775712fbe068a098155d6e93f6808233cf0:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/gnutls
 * [new ref]         21532775712fbe068a098155d6e93f6808233cf0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2153277 bump release for test build