[actions] skip pack tests

Author: ljharb

.github/workflows/node-pretest.yml

@@ -5,3 +5,5 @@ on: [pull_request, push]
 jobs:
   tests:
     uses: ljharb/actions/.github/workflows/pretest.yml@main
+    with:
+      skip-pack: true # `npm run tests-only` fails in node 15+ without NODE_OPTIONS=--unhandled-rejections=none, but older nodes throw for unrecognized NODE_OPTIONS