Released an updated version of the Alpha version of API Gateway

## Announcement Released an updated version of the Alpha version of API Gateway. To provide feedback or to log issues with this release, see [Getting support](https://cloud.google.com/api-gateway/docs/getting-support). ## Feature Newly created gateways now have an updated default hostname pattern: `https://GATEWAY_ID-HASH.REGION_CODE.gateway.dev` where **GATEWAY\_ID** is the name of the gateway, **HASH** is the unique hash code generated when you deployed the gateway, and **REGION\_CODE** is the code for the Google Cloud region where the gateway is deployed. For more information, see [Deploying an API to a gateway](https://cloud.google.com/api-gateway/docs/deploying-api). ## Feature OpenAPI specifications for API configs no longer require the `host` property. You can either omit the `host` property entirely or set it to the DNS name of the deployed API. API providers often set it to the DNS name when sharing the OpenAPI Spec with their API consumers. However, the value of the `host` property is not enforced by API Gateway. Do not set the `host` property to **null** or an empty value, as this will result in an error. For more information, see [OpenAPI overview](https://cloud.google.com/api-gateway/docs/openapi-overview). ## Feature Updated the [REST API reference](https://cloud.google.com/api-gateway/docs/reference/rest) to the latest Alpha version. ## Issue When creating an API config, and in particular the _first_ config for a new service, the operation may take several minutes to complete as the config is propagated to downstream systems. Creation of a complex API config could take up to ten minutes to complete successfully. ## Issue When creating a gateway, permissions can take more than a minute to propagate through the system. Therefore, you might see a "missing tokens" error when making a request to an API. If you see this error, wait several minutes, then retry the request.