update events for GH actions to include PRs (#511)

* update events for GH actions to include PRs

* change action events to pull_request only

.github/workflows/lint.yml

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

.github/workflows/test.yml

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