$ git clone -n https://src.fedoraproject.org/rpms/rust-filetreelist.git /var/lib/mock/f40-build-2061846-49167/root/chroot_tmpdir/scmroot/rust-filetreelist
Cloning into '/var/lib/mock/f40-build-2061846-49167/root/chroot_tmpdir/scmroot/rust-filetreelist'...
$ git fetch origin dd15e04f7968c99c84553e17b6389d21166acc63:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-filetreelist
 * [new ref]         dd15e04f7968c99c84553e17b6389d21166acc63 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at dd15e04 Update to version 0.5.0; Fixes RHBZ#2119184