Use NGF Logger in Client-Go Library

[pleshakov]

Initialize klog to NGF logger so that client-go logs become consistent with NGF loggers.

So that we avoid inconsistencies like below:

I0927 21:14:42.702979       7 leaderelection.go:250] attempting to acquire leader lease nginx-gateway/nginx-gateway-leader-election...
{"level":"info","ts":"2023-09-27T21:14:42Z","logger":"statusUpdater","msg":"Skipping updating Gateway API status because not leader"}
{"level":"info","ts":"2023-09-27T21:14:42Z","logger":"statusUpdater","msg":"Skipping updating Nginx Gateway status because not leader"}
I0927 21:15:04.509435       7 leaderelection.go:260] successfully acquired lease nginx-gateway/nginx-gateway-leader-election
{"level":"info","ts":"2023-09-27T21:15:04Z","logger":"leaderElector","msg":"Started leading"}

where some lines are text klog logs, others - structured NGF logs

Acceptance criteria:

• Use https://pkg.go.dev/k8s.io/klog/v2#SetLogger
• Ensure NGF log level works well with klog level
• Update logging guidelines -- https://github.com/nginxinc/nginx-gateway-fabric/blob/main/docs/developer/logging-guidelines.md#external-libraries