$ git clone -n https://src.fedoraproject.org/rpms/R-biglm.git /var/lib/mock/f40-build-789300-135702/root/chroot_tmpdir/scmroot/R-biglm
Cloning into '/var/lib/mock/f40-build-789300-135702/root/chroot_tmpdir/scmroot/R-biglm'...
$ git fetch origin b72025899e393912ace4b2ea2f5a05da85d6453e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-biglm
 * [new ref]         b72025899e393912ace4b2ea2f5a05da85d6453e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b720258 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild