App Engine - Flexible Go - August 20th, 2026 [Feature]

## Feature Feature Starting from August 2026, to provide modern security patches and support for MySQL 8.4 and later, the App Engine flexible environment uses Cloud SQL Auth Proxy v2 as the built-in sidecar container for connections to Cloud SQL. To use the latest Cloud SQL Auth Proxy container immediately, restart your VMs or deploy a new version of your application.