$ git clone -n https://github.com/xcp-ng-rpms/libarchive.git /var/lib/mock/v8.3-u-pcoval2-10368-28931/root/chroot_tmpdir/scmroot/libarchive
Cloning into '/var/lib/mock/v8.3-u-pcoval2-10368-28931/root/chroot_tmpdir/scmroot/libarchive'...
$ git fetch origin 7155257d48fbaa7514ebfb2a2a324a0182b953ec:KOJI_FETCH_HEAD
From https://github.com/xcp-ng-rpms/libarchive
 * [new ref]         7155257d48fbaa7514ebfb2a2a324a0182b953ec -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 7155257 bump release for test build