$ git clone -n https://src.fedoraproject.org/rpms/nbdkit.git /var/lib/mock/f40-build-2424966-60598/root/chroot_tmpdir/scmroot/nbdkit
Cloning into '/var/lib/mock/f40-build-2424966-60598/root/chroot_tmpdir/scmroot/nbdkit'...
$ git fetch origin d38d28e5e0203df12f84736067f227373096e068:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/nbdkit
 * [new ref]         d38d28e5e0203df12f84736067f227373096e068 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d38d28e +BR bash-completion-devel