chore: revert test-spec to single node --test invocation

Author: nfriedly

package.json

@@ -38,7 +38,7 @@
     "pre-commit": "npm run autofix && npm test",
     "lint": "eslint .",
     "autofix": "eslint . --fix",
-    "test-spec": "for f in test/*spec.js; do timeout 20s node --test \"$f\" || exit 1; done",
+    "test-spec": "node --test test/*spec.js",
     "test-perf": "node test/performance.js"
   },
   "license": "AGPL-3.0",