$ git clone -n https://src.fedoraproject.org/rpms/R-knitr.git /var/lib/mock/f39-build-1544795-36669/root/chroot_tmpdir/scmroot/R-knitr
Cloning into '/var/lib/mock/f39-build-1544795-36669/root/chroot_tmpdir/scmroot/R-knitr'...
$ git fetch origin fe36e4c63c3c728b131d860659f3cf3e2a6624ce:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-knitr
 * [new ref]         fe36e4c63c3c728b131d860659f3cf3e2a6624ce -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fe36e4c Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild