$ git clone -n https://src.fedoraproject.org/rpms/R-vctrs.git /var/lib/mock/f40-build-789247-135690/root/chroot_tmpdir/scmroot/R-vctrs
Cloning into '/var/lib/mock/f40-build-789247-135690/root/chroot_tmpdir/scmroot/R-vctrs'...
$ git fetch origin 441e31e0745b191c997272861b5ffdbcc03a97c0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-vctrs
 * [new ref]         441e31e0745b191c997272861b5ffdbcc03a97c0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 441e31e Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild