chore(deps): bump cloud-sql-connectors/cloud-sql-proxy

Bumps the docker_dev group in /deployment/dev/backstage with 1 update: [cloud-sql-connectors/cloud-sql-proxy](https://github.com/GoogleCloudPlatform/cloud-sql-proxy).


Updates `cloud-sql-connectors/cloud-sql-proxy` from 2.14.2 to 2.14.3
- [Release notes](https://github.com/GoogleCloudPlatform/cloud-sql-proxy/releases)
- [Changelog](https://github.com/GoogleCloudPlatform/cloud-sql-proxy/blob/main/CHANGELOG.md)
- [Commits](GoogleCloudPlatform/cloud-sql-proxy@v2.14.2...v2.14.3)

---
updated-dependencies:
- dependency-name: cloud-sql-connectors/cloud-sql-proxy
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: docker_dev
...

Signed-off-by: dependabot[bot] <[email protected]>

deployment/dev/backstage/backstage.yaml

@@ -90,7 +90,7 @@ spec:
         - name: cloud-sql-proxy
           # It is recommended to use the latest version of the Cloud SQL Auth Proxy
           # Make sure to update on a regular schedule!
-          image: gcr.io/cloud-sql-connectors/cloud-sql-proxy:2.14.2
+          image: gcr.io/cloud-sql-connectors/cloud-sql-proxy:2.14.3
           args:
             # If connecting from a VPC-native GKE cluster, you can use the
             # following flag to have the proxy connect over private IP