message: docs: update contributing path in README
diff: @@ -79,7 +79,7 @@ More Information: [Google Cloud Platform Launch Stages][launch_stages]
  ## Contributing
  -Contributions welcome! See the [Contributing Guide](https://github.com/googleapis/nodejs-pubsub/blob/master/.github/CONTRIBUTING.md).
  +Contributions welcome! See the [Contributing Guide](https://github.com/googleapis/nodejs-pubsub/blob/master/CONTRIBUTING.md).
  ## License
  