$ git clone -n https://github.com/xcp-ng-rpms/xs-opam-repo /var/lib/mock/v9.0-u-ydi1-11215-29595/root/chroot_tmpdir/scmroot/xs-opam-repo
Cloning into '/var/lib/mock/v9.0-u-ydi1-11215-29595/root/chroot_tmpdir/scmroot/xs-opam-repo'...
$ git fetch origin f474332c3b9acbf983674f99a187504296b2fba0:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/xs-opam-repo
 * [new ref]         f474332c3b9acbf983674f99a187504296b2fba0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f474332 bump release for test build