$ git clone -n https://src.fedoraproject.org/rpms/golang-gopkg-warnings-0.git /var/lib/mock/f41-build-1036621-18741/root/chroot_tmpdir/scmroot/golang-gopkg-warnings-0
Cloning into '/var/lib/mock/f41-build-1036621-18741/root/chroot_tmpdir/scmroot/golang-gopkg-warnings-0'...
$ git fetch origin dff0b21a515ef5a5e8fa2504702925325c5034ac:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-gopkg-warnings-0
 * [new ref]         dff0b21a515ef5a5e8fa2504702925325c5034ac -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dff0b21 Fix FTBFS