$ git clone -n https://src.fedoraproject.org/rpms/kjumpingcube.git /var/lib/mock/f45-build-15234-471/root/chroot_tmpdir/scmroot/kjumpingcube
Cloning into '/var/lib/mock/f45-build-15234-471/root/chroot_tmpdir/scmroot/kjumpingcube'...
$ git fetch origin 51c09e7ede1df2a9ca995c53061ff10d213df8cc:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kjumpingcube
 * [new ref]         51c09e7ede1df2a9ca995c53061ff10d213df8cc -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 51c09e7 26.08.1