$ git clone -n https://src.fedoraproject.org/rpms/golang-github-nats-io-nkeys.git /var/lib/mock/f40-build-2001552-44602/root/chroot_tmpdir/scmroot/golang-github-nats-io-nkeys
Cloning into '/var/lib/mock/f40-build-2001552-44602/root/chroot_tmpdir/scmroot/golang-github-nats-io-nkeys'...
$ git fetch origin 1063d86c8866c1a5ae29fe95f9139c5bf221fad2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-nats-io-nkeys
 * [new ref]         1063d86c8866c1a5ae29fe95f9139c5bf221fad2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1063d86 update to 0.4.6, close rhbz#2246023