[kutil] Fix failing heap allocator tests

The tests clearly haven't even been built in a while. I've added a
helper script to the project root. Also added a kassert() handler that
will allow tests to catch or fail on asserts.

test.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+
+set -o errexit
+
+ROOT=$(realpath $(dirname $0))
+BUILD="${ROOT}/build"
+TESTS="${BUILD}/native/tests" 
+
+ninja -C "${BUILD}" "${TESTS}"
+"${TESTS}" $*