chore(deps): update dependency @types/mocha to v9 (#782)

Author: renovate-bot

packages/google-cloud-translate/package.json

@@ -57,7 +57,7 @@
   },
   "devDependencies": {
     "@types/extend": "^3.0.0",
-    "@types/mocha": "^8.0.0",
+    "@types/mocha": "^9.0.0",
     "@types/node": "^16.0.0",
     "@types/proxyquire": "^1.3.28",
     "@types/request": "^2.47.1",