ci: also trigger workflow on PRs

This should allow PRs from forks to run checks: https://help.github.com/en/actions/automating-your-workflow-with-github-actions/events-that-trigger-workflows#pull-request-events-for-forked-repositories

Might need to restrict the events that trigger it though, it sounds like even stuff like labels and assignments will trigger the workflow: https://help.github.com/en/actions/automating-your-workflow-with-github-actions/events-that-trigger-workflows#pull-request-event-pull_request

Author: filipesilva

.github/workflows/nodejs.yml

@@ -1,6 +1,6 @@
 name: Node CI
 
-on: [push]
+on: [push, pull_request]
 
 jobs:
   test: