$ git clone -n https://src.fedoraproject.org/rpms/R-remotes.git /var/lib/mock/f38-build-side-42-init-devel-663528-26641/root/chroot_tmpdir/scmroot/R-remotes
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-663528-26641/root/chroot_tmpdir/scmroot/R-remotes'...
$ git fetch origin 8627810e27bb8950d45e6f0144e30336d6ac9e6e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-remotes
 * [new ref]         8627810e27bb8950d45e6f0144e30336d6ac9e6e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8627810 Rebuilt for https://fedoraproject.org/wiki/Fedora_38_Mass_Rebuild