Use large GitHub runner (#48)

build(runner): change runner groups

.github/workflows/validate-pubnub-yml.yml

@@ -7,13 +7,14 @@ on: [push]
 jobs:
   build:
       name: Validate PubNub yml
-      runs-on: ubuntu-latest
+    runs-on:
+      group: Default
       steps:
-        - uses: actions/checkout@v2
+        - uses: actions/checkout@v4
         - name: Use Node.js
-          uses: actions/setup-node@v1
+          uses: actions/setup-node@v4
           with:
-            node-version: '12.x'
+            node-version: '18.x'
         - name: Install dependencies
           run: |
             npm install ajv@6.12.6