kube-controllers: pprof is enabled on /metrics server port.

[xinfengliu]

In kube-controllers/cmd/kube-controllers/main.go, there's an import _ "net/http/pprof", this causes /debug/pprof emerges in any started http server such as server for serving /metrics (default at port 9094) even if DebugProfilePort is not set.

Expected Behavior

/debug/pprof is not enabled on Calico kube-controllers's /metrics server port

Current Behavior

/debug/pprof is enabled on Calico kube-controllers's /metrics server port

Possible Solution

Not sure if import _ "net/http/pprof" is necessary, I see currently if DebugProfilePort is not zero, github.com/pkg/profile is used to write profile data to local disk.

Steps to Reproduce (for bugs)

1. Deploy Calico and /metrics is enabled in kube-controllers (this is default).
2. Access http://<calico-kube-controllers IP>:9094/debug/pprof

Context

Exposing pprof by default outside the host OS is considered a security issue by organizations which have high security requirements.

Your Environment

• Calico version v3.27.0
• Orchestrator version (e.g. kubernetes, mesos, rkt): kubernetes
• Operating System and version: Rocky Linux 8.6
• Link to your project (optional):