$ git clone -n https://github.com/xcp-ng-rpms/wget.git /var/lib/mock/v8.3-incoming-9099-27939/root/chroot_tmpdir/scmroot/wget
Cloning into '/var/lib/mock/v8.3-incoming-9099-27939/root/chroot_tmpdir/scmroot/wget'...
$ git fetch origin ee924685d2266289c6a1ead5e8d68f3c5d3a9b50:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/wget
 * [new ref]         ee924685d2266289c6a1ead5e8d68f3c5d3a9b50 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ee92468 Import wget-1.21.3-2.xs8.src.rpm