chore: use Node.js v12 for Firebase functions on {code,docs}-angularjs-org

Author: gkalpak

Diff for: scripts/code.angularjs.org-firebase/functions/package.json

@@ -2,7 +2,7 @@
   "name": "functions-firebase-code.angularjs.org",
   "description": "Cloud Functions to serve files from gcs to code.angularjs.org",
   "engines": {
-    "node": "10"
+    "node": "12"
   },
   "dependencies": {
     "@google-cloud/storage": "^4.7.0",

Diff for: scripts/docs.angularjs.org-firebase/functions/package.json

@@ -2,8 +2,8 @@
   "name": "functions",
   "description": "Cloud Functions for Firebase",
   "engines": {
-    "node": "10"
-  },  
+    "node": "12"
+  },
   "scripts": {
     "lint": "eslint .",
     "serve": "firebase serve --only functions",