$ git clone -n https://src.fedoraproject.org/rpms/erlang.git /var/lib/mock/f40-build-789722-135964/root/chroot_tmpdir/scmroot/erlang
Cloning into '/var/lib/mock/f40-build-789722-135964/root/chroot_tmpdir/scmroot/erlang'...
$ git fetch origin d2e9015f83b074984280f16d50ea1c4f8fb52174:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/erlang
 * [new ref]         d2e9015f83b074984280f16d50ea1c4f8fb52174 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d2e9015 Erlang ver. 26.2.2