$ git clone -n https://src.fedoraproject.org/rpms/river.git /var/lib/mock/f41-build-692356-12741/root/chroot_tmpdir/scmroot/river
Cloning into '/var/lib/mock/f41-build-692356-12741/root/chroot_tmpdir/scmroot/river'...
$ git fetch origin 8b65e2939e5c5ea1c6e1b68db5150aaa4c982fa9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/river
 * [new ref]         8b65e2939e5c5ea1c6e1b68db5150aaa4c982fa9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8b65e29 Update to 0.3.1 (#2281411)