fix(docs): move to new client docs URL (#239)

Author: bcoe

packages/google-cloud-texttospeech/.repo-metadata.json

@@ -2,12 +2,12 @@
   "name": "text-to-speech",
   "name_pretty": "Google Cloud Text-to-Speech",
   "product_documentation": "https://cloud.google.com/text-to-speech",
-  "client_documentation": "https://cloud.google.com/nodejs/docs/reference/text-to-speech/latest/",
+  "client_documentation": "https://googleapis.dev/nodejs/text-to-speech/latest",
   "issue_tracker": "https://issuetracker.google.com/savedsearches/5235428",
   "release_level": "alpha",
   "language": "nodejs",
   "repo": "googleapis/nodejs-text-to-speech",
   "distribution_name": "@google-cloud/text-to-speech",
   "api_id": "texttospeech.googleapis.com",
   "requires_billing": true
-}
+}

packages/google-cloud-texttospeech/README.md

@@ -133,7 +133,7 @@ Apache Version 2.0
 
 See [LICENSE](https://github.com/googleapis/nodejs-text-to-speech/blob/master/LICENSE)
 
-[client-docs]: https://cloud.google.com/nodejs/docs/reference/text-to-speech/latest/
+[client-docs]: https://googleapis.dev/nodejs/text-to-speech/latest
 [product-docs]: https://cloud.google.com/text-to-speech
 [shell_img]: https://gstatic.com/cloudssh/images/open-btn.png
 [projects]: https://console.cloud.google.com/project