$ git clone -n https://github.com/xcp-ng-rpms/libevent.git /var/lib/mock/v8.3-u-pcoval2-10378-28940/root/chroot_tmpdir/scmroot/libevent
Cloning into '/var/lib/mock/v8.3-u-pcoval2-10378-28940/root/chroot_tmpdir/scmroot/libevent'...
$ git fetch origin 59677b3763c95d74f2762f533494fa006d56f25e:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/libevent
 * [new ref]         59677b3763c95d74f2762f533494fa006d56f25e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 59677b3 bump release for test build