Bug Description

When started with "--prometheus and --health-check, the HTTP server listens for requests on localhost, but it should listen on anyhost. Otherwise, it cannon be accessed using the Pod IP (from Prometheus, kubelet, and Istio).

How to reproduce

1. Run the Pod with --health-check
2. Create an ephemeral container with debug and run curl localhost:9090/readiness and curl <pod IP>:9090/readiness. The latter won't work.

Environment

• GKE 1.23 with COS containerd nodes
• Cloud SQL Proxy version: docker container built from the v2.0.0.preview.0 tag, targeting Linux amd64

EDIT: I can open a pull request if you want. I tested it, and it worked by replacing localhost with 0.0.0.0 in the HTTP server.