$ git clone -n https://src.fedoraproject.org/rpms/R-sp /var/lib/mock/f39-build-1585608-38146/root/chroot_tmpdir/scmroot/R-sp
Cloning into '/var/lib/mock/f39-build-1585608-38146/root/chroot_tmpdir/scmroot/R-sp'...
$ git fetch origin bc8c9c8e7f847c874af5b95aecd657d5f8195ffa:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-sp
 * [new ref]         bc8c9c8e7f847c874af5b95aecd657d5f8195ffa -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bc8c9c8 Update to 2.0.0