$ git clone -n https://github.com/xcp-ng-rpms/xapi.git /var/lib/mock/v8.3-u-asultanov2-9010-27907/root/chroot_tmpdir/scmroot/xapi
Cloning into '/var/lib/mock/v8.3-u-asultanov2-9010-27907/root/chroot_tmpdir/scmroot/xapi'...
$ git fetch origin 56dc35fce37e0bd0752adb5086b098cd1d0e9d29:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xapi
 * [new ref]         56dc35fce37e0bd0752adb5086b098cd1d0e9d29 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 56dc35f bump release for test build