chore: update engines node version to 22

Author: angelcaamal

document-ai/package.json

@@ -4,7 +4,7 @@
   "license": "Apache-2.0",
   "author": "Google LLC",
   "engines": {
-    "node": ">=16.0.0"
+    "node": ">= 22.0.0"
   },
   "files": [
     "*.js"

eventarc/generic/package.json

@@ -10,7 +10,7 @@
     "url": "https://github.com/GoogleCloudPlatform/nodejs-docs-samples.git"
   },
   "engines": {
-    "node": ">= 12.0.0"
+    "node": ">=22.0.0"
   },
   "scripts": {
     "start": "node index.js",