properly exclude stacktests in make test
properly exclude stacktests in make test

should have been part of #830

replay/metrictank,raintank/raintank-metric,replay/metrictank,replay/metrictank,raintank/metrictank,replay/metrictank,raintank/raintank-metric,raintank/metrictank,raintank/metrictank,raintank/metrictank,raintank/raintank-metric