fix(docs): bump the release level to beta (#229)

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

@@ -3,10 +3,10 @@
   "name_pretty": "Google Cloud Internet of Things (IoT) Core",
   "product_documentation": "https://cloud.google.com/iot",
   "client_documentation": "https://googleapis.dev/nodejs/iot/latest",
-  "release_level": "alpha",
+  "release_level": "beta",
   "language": "nodejs",
   "repo": "googleapis/nodejs-iot",
   "distribution_name": "@google-cloud/iot",
   "api_id": "cloudiot.googleapis.com",
   "requires_billing": true
-}
+}

packages/google-cloud-iot/README.md

@@ -4,7 +4,7 @@
 
 # [Google Cloud Internet of Things (IoT) Core: Node.js Client](https://github.com/googleapis/nodejs-iot)
 
-[![release level](https://img.shields.io/badge/release%20level-alpha-orange.svg?style=flat)](https://cloud.google.com/terms/launch-stages)
+[![release level](https://img.shields.io/badge/release%20level-beta-yellow.svg?style=flat)](https://cloud.google.com/terms/launch-stages)
 [![npm version](https://img.shields.io/npm/v/@google-cloud/iot.svg)](https://www.npmjs.org/package/@google-cloud/iot)
 [![codecov](https://img.shields.io/codecov/c/github/googleapis/nodejs-iot/master.svg?style=flat)](https://codecov.io/gh/googleapis/nodejs-iot)
 
@@ -95,10 +95,11 @@ This library follows [Semantic Versioning](http://semver.org/).
 
 
 
+This library is considered to be in **beta**. This means it is expected to be
+mostly stable while we work toward a general availability release; however,
+complete stability is not guaranteed. We will address issues and requests
+against beta libraries with a high priority.
 
-This library is considered to be in **alpha**. This means it is still a
-work-in-progress and under active development. Any release is subject to
-backwards-incompatible changes at any time.