fix: .env is located next to package.json

tests/binary_test/run_parent_env_binary.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+binary="$1"
+output="$(${binary})"
+
+if [[ ${output} != "from-parent-dotenv" ]]; then
+  echo "Expected .env value from parent directory, got: ${output}" >&2
+  exit 1
+fi