chore: update repo metadata (#131)

* chore: update repo metadata

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: Jeff Ching <chingor@google.com>

packages/google-devtools-artifactregistry/.repo-metadata.json

@@ -1,6 +1,6 @@
 {
   "default_version": "v1",
-  "release_level": "ga",
+  "release_level": "stable",
   "requires_billing": true,
   "client_documentation": "https://cloud.google.com/nodejs/docs/reference/artifact-registry/latest",
   "codeowner_team": "@googleapis/aap-dpes",

packages/google-devtools-artifactregistry/README.md

@@ -4,7 +4,7 @@
 
 # [Artifact Registry: Node.js Client](https://github.com/googleapis/nodejs-artifact-registry)
 
-[![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)
+[![release level](https://img.shields.io/badge/release%20level-stable-brightgreen.svg?style=flat)](https://cloud.google.com/terms/launch-stages)
 [![npm version](https://img.shields.io/npm/v/@google-cloud/artifact-registry.svg)](https://www.npmjs.org/package/@google-cloud/artifact-registry)
 
 
@@ -121,18 +121,17 @@ for versions compatible with Node.js 8.
 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
+
+This library is considered to be **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
+an extensive deprecation period. Issues and requests against **stable** libraries
 are addressed with the highest priority.
 
 
 
 
 
 
-
 More Information: [Google Cloud Platform Launch Stages][launch_stages]
 
 [launch_stages]: https://cloud.google.com/terms/launch-stages