$ git clone -n https://src.fedoraproject.org/rpms/libnfs.git /var/lib/mock/f45-build-16637-489/root/chroot_tmpdir/scmroot/libnfs
Cloning into '/var/lib/mock/f45-build-16637-489/root/chroot_tmpdir/scmroot/libnfs'...
$ git fetch origin 3607ab7448b536112920c93a3e0bff45e387120d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/libnfs
 * [new ref]         3607ab7448b536112920c93a3e0bff45e387120d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3607ab7 Update to 7.0.0 (RHBZ#2512689)