Merge branch 'ash2k/arm-support' into 'master'

Document ARM architecture support in agentk

See merge request gitlab-org/gitlab!80987

doc/user/clusters/agent/install/index.md

@@ -8,6 +8,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 
 > - [Moved](https://gitlab.com/groups/gitlab-org/-/epics/6290) from GitLab Premium to GitLab Free in 14.5.
 > - [Introduced](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent/-/merge_requests/594) multi-arch images in GitLab 14.8. The first multi-arch release is `v14.8.1`. It supports AMD64 and ARM64 architectures.
+> - [Introduced](https://gitlab.com/gitlab-org/cluster-integration/gitlab-agent/-/merge_requests/603) ARM architecture support in GitLab 14.9.
 
 To connect a Kubernetes cluster to GitLab, you must install an agent in your cluster.