$ git clone -n https://src.fedoraproject.org/rpms/tinc.git /var/lib/mock/f41-build-side-1-2670619-29060/root/chroot_tmpdir/scmroot/tinc
Cloning into '/var/lib/mock/f41-build-side-1-2670619-29060/root/chroot_tmpdir/scmroot/tinc'...
$ git fetch origin b7efc113b68962bb7f171c072df286b74571d241:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tinc
 * [new ref]         b7efc113b68962bb7f171c072df286b74571d241 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b7efc11 convert GPLv2+ license to SPDX