App Engine now sets the automatic scaling maximum instances default for standard environment deployments to 20

## Feature App Engine now sets the automatic scaling maximum instances default for standard environment deployments to 20\. This change doesn't impact existing apps. To override the default, specify a new [max\_instances](https://cloud.google.com/appengine/docs/standard/reference/app-yaml#scaling%5Felements) value in your `app.yaml` file, and deploy a new version or redeploy over an existing version.