$ git clone -n https://github.com/xcp-ng-rpms/expat /var/lib/mock/v8.3-u-prebuild-9185-27988/root/chroot_tmpdir/scmroot/expat
Cloning into '/var/lib/mock/v8.3-u-prebuild-9185-27988/root/chroot_tmpdir/scmroot/expat'...
$ git fetch origin 410814ebf7f453647e75d09ed9bb30c08414f4c2:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/expat
 * [new ref]         410814ebf7f453647e75d09ed9bb30c08414f4c2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 410814e bump release for test build