$ git clone -n https://src.fedoraproject.org/rpms/erlang-merge_index.git /var/lib/mock/f40-build-2589228-62566/root/chroot_tmpdir/scmroot/erlang-merge_index
Cloning into '/var/lib/mock/f40-build-2589228-62566/root/chroot_tmpdir/scmroot/erlang-merge_index'...
$ git fetch origin 6e7a7789c813b48f56bcd73947294f06bbf943a1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/erlang-merge_index
 * [new ref]         6e7a7789c813b48f56bcd73947294f06bbf943a1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6e7a778 Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild