$ git clone -n https://src.fedoraproject.org/rpms/diffpdf.git /var/lib/mock/f40-build-2434014-60729/root/chroot_tmpdir/scmroot/diffpdf
Cloning into '/var/lib/mock/f40-build-2434014-60729/root/chroot_tmpdir/scmroot/diffpdf'...
$ git fetch origin e422fded759671a5dc90757a28a4e14a485e68f4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/diffpdf
 * [new ref]         e422fded759671a5dc90757a28a4e14a485e68f4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e422fde Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild