$ git clone -n https://src.fedoraproject.org/rpms/libisds.git /var/lib/mock/f40-build-2219788-52642/root/chroot_tmpdir/scmroot/libisds
Cloning into '/var/lib/mock/f40-build-2219788-52642/root/chroot_tmpdir/scmroot/libisds'...
$ git fetch origin b34df8cf32eccbac7074e6f1e05ce5c30da39de5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libisds
 * [new ref]         b34df8cf32eccbac7074e6f1e05ce5c30da39de5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b34df8c Adapt to changes in libxml2-2.12.0