$ git clone -n https://src.fedoraproject.org/rpms/R-jpeg.git /var/lib/mock/f40-build-789472-135730/root/chroot_tmpdir/scmroot/R-jpeg
Cloning into '/var/lib/mock/f40-build-789472-135730/root/chroot_tmpdir/scmroot/R-jpeg'...
$ git fetch origin 836748f68af6cb56c6eab2d71bd87d661bd04384:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-jpeg
 * [new ref]         836748f68af6cb56c6eab2d71bd87d661bd04384 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 836748f Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild