$ git clone -n https://src.fedoraproject.org/rpms/R-stringi /var/lib/mock/f39-build-1582020-38102/root/chroot_tmpdir/scmroot/R-stringi
Cloning into '/var/lib/mock/f39-build-1582020-38102/root/chroot_tmpdir/scmroot/R-stringi'...
$ git fetch origin 9a6e2203773816f514fe38d0e4b9a53d95abb71c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-stringi
 * [new ref]         9a6e2203773816f514fe38d0e4b9a53d95abb71c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9a6e220 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild