$ git clone -n https://src.fedoraproject.org/rpms/jsch.git /var/lib/mock/f42-build-3364936-45045/root/chroot_tmpdir/scmroot/jsch
Cloning into '/var/lib/mock/f42-build-3364936-45045/root/chroot_tmpdir/scmroot/jsch'...
$ git fetch origin 1820ce99a37f97ef1eaccecd8246e514c12af1ec:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jsch
 * [new ref]         1820ce99a37f97ef1eaccecd8246e514c12af1ec -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1820ce9 Remove javadoc subpackage