$ git clone -n https://github.com/xcp-ng-rpms/mdadm.git /var/lib/mock/v8.3-incoming-9024-27901/root/chroot_tmpdir/scmroot/mdadm
Cloning into '/var/lib/mock/v8.3-incoming-9024-27901/root/chroot_tmpdir/scmroot/mdadm'...
$ git fetch origin 9b97a4f3aa78965f8bac1b13274cccc817e5c696:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/mdadm
 * [new ref]         9b97a4f3aa78965f8bac1b13274cccc817e5c696 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9b97a4f Import mdadm-4.2-5.xs8.src.rpm