build!: update library to use Node 12 (#288)

* feat!: Update library to use Node 12

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

packages/google-cloud-dialogflow-cx/package.json

@@ -50,28 +50,28 @@
     "samples-test": "cd samples/ && npm link ../ && npm test"
   },
   "dependencies": {
-    "google-gax": "^2.24.1"
+    "google-gax": "^3.0.1"
   },
   "devDependencies": {
     "@types/mocha": "^9.0.0",
     "@types/node": "^16.0.0",
     "@types/sinon": "^10.0.0",
     "c8": "^7.3.0",
-    "gts": "^3.0.0",
+    "gts": "^3.1.0",
     "jsdoc": "^3.6.5",
     "jsdoc-fresh": "^1.0.2",
     "jsdoc-region-tag": "^1.0.4",
     "linkinator": "^2.1.1",
-    "mocha": "^8.1.1",
+    "mocha": "^9.2.2",
     "null-loader": "^4.0.0",
     "pack-n-play": "^1.0.0-2",
     "sinon": "^14.0.0",
     "ts-loader": "^9.0.0",
-    "typescript": "^3.9.7",
+    "typescript": "^4.6.4",
     "webpack": "^5.0.0",
     "webpack-cli": "^4.0.0"
   },
   "engines": {
-    "node": ">=10.0.0"
+    "node": ">=12.0.0"
   }
 }

packages/google-cloud-dialogflow-cx/samples/package.json

@@ -4,7 +4,7 @@
   "license": "Apache-2.0",
   "author": "Google LLC",
   "engines": {
-    "node": ">=10"
+    "node": ">=12.0.0"
   },
   "files": [
     "*.js"