fix: flag module as GA

.repo-metadata.json

@@ -4,7 +4,7 @@
   "product_documentation": "https://cloud.google.com/tpu/",
   "client_documentation": "https://cloud.google.com/nodejs/docs/reference/tpu/latest",
   "issue_tracker": "https://github.com/googleapis/nodejs-cloud-tpu/issues",
-  "release_level": "BETA",
+  "release_level": "ga",
   "language": "nodejs",
   "repo": "googleapis/nodejs-cloud-tpu",
   "distribution_name": "@google-cloud/tpu",

README.md

@@ -4,7 +4,7 @@
 
 # [Cloud TPU: Node.js Client](https://github.com/googleapis/nodejs-cloud-tpu)
 
-[![release level](https://img.shields.io/badge/release%20level-beta-yellow.svg?style=flat)](https://cloud.google.com/terms/launch-stages)
+[![release level](https://img.shields.io/badge/release%20level-general%20availability%20%28GA%29-brightgreen.svg?style=flat)](https://cloud.google.com/terms/launch-stages)
 [![npm version](https://img.shields.io/npm/v/@google-cloud/tpu.svg)](https://www.npmjs.org/package/@google-cloud/tpu)
 [![codecov](https://img.shields.io/codecov/c/github/googleapis/nodejs-cloud-tpu/main.svg?style=flat)](https://codecov.io/gh/googleapis/nodejs-cloud-tpu)
 
@@ -121,6 +121,12 @@ _Legacy Node.js versions are supported as a best effort:_
 This library follows [Semantic Versioning](http://semver.org/).
 
 
+This library is considered to be **General Availability (GA)**. This means it
+is stable; the code surface will not change in backwards-incompatible ways
+unless absolutely necessary (e.g. because of critical security issues) or with
+an extensive deprecation period. Issues and requests against **GA** libraries
+are addressed with the highest priority.
+