$ git clone -n https://src.fedoraproject.org/rpms/diffmark.git /var/lib/mock/f40-build-746808-112860/root/chroot_tmpdir/scmroot/diffmark
Cloning into '/var/lib/mock/f40-build-746808-112860/root/chroot_tmpdir/scmroot/diffmark'...
$ git fetch origin f78fd25c3577ca38cfc4cddb721d677265093194:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/diffmark
 * [new ref]         f78fd25c3577ca38cfc4cddb721d677265093194 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f78fd25 Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild