$ git clone -n https://src.fedoraproject.org/rpms/tang.git /var/lib/mock/f42-build-3289797-41410/root/chroot_tmpdir/scmroot/tang
Cloning into '/var/lib/mock/f42-build-3289797-41410/root/chroot_tmpdir/scmroot/tang'...
$ git fetch origin 48e3b12194fd363a83bb7408662dda3ea174752b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tang
 * [new ref]         48e3b12194fd363a83bb7408662dda3ea174752b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 48e3b12 Drop call to %sysusers_create_compat