$ git clone -n https://src.fedoraproject.org/rpms/R-readr.git /var/lib/mock/f39-build-1570273-37756/root/chroot_tmpdir/scmroot/R-readr
Cloning into '/var/lib/mock/f39-build-1570273-37756/root/chroot_tmpdir/scmroot/R-readr'...
$ git fetch origin aedf29d85b23c32f57665685dff0d0caf7f31a72:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-readr
 * [new ref]         aedf29d85b23c32f57665685dff0d0caf7f31a72 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aedf29d Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild