$ git clone -n https://github.com/xcp-ng-rpms/dummypkg.git /var/lib/mock/v8.3-u-stormi1-8821-27766/root/chroot_tmpdir/scmroot/dummypkg
Cloning into '/var/lib/mock/v8.3-u-stormi1-8821-27766/root/chroot_tmpdir/scmroot/dummypkg'...
$ git fetch origin 9ea931ee100642b4d20b80ee593382b00f1fb3b6:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/dummypkg
 * [new ref]         9ea931ee100642b4d20b80ee593382b00f1fb3b6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9ea931e Set team owner