$ git clone -n https://src.fedoraproject.org/rpms/golang-gonum-1.git /var/lib/mock/f41-build-1036535-18736/root/chroot_tmpdir/scmroot/golang-gonum-1
Cloning into '/var/lib/mock/f41-build-1036535-18736/root/chroot_tmpdir/scmroot/golang-gonum-1'...
$ git fetch origin 8c0d9cc9f0197dafd02d2bbc44f718e76a277506:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-gonum-1
 * [new ref]         8c0d9cc9f0197dafd02d2bbc44f718e76a277506 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8c0d9cc Fix FTBFS