kgo: add args and provide current defaults via env

[pmalek]

What this PR does / why we need it:

Provide args section KGO chart.

This will help users to migrate from pre 1.2 versions which didn't have the ability to use the env vars (implemented in https://github.com/Kong/gateway-operator-archive/pull/1616).

The reason for this is that pre 1.2 had ControlPlane and GatewayConfiguration in v1alpha1 and 1.2+ have those CRDs only defined in v1beta1 which makes it impossible to easily migrate using this chart which didn't provide users a way to disable Gateway and ControlPlane controllers to prevent errors like these:

manager {"level":"error","ts":"2024-04-18T12:33:54Z","msg":"failed to run manager","error":"no matches for kind \"ControlPlane\" in version \"gateway-operator.konghq.com/v1beta1\"","stacktrace":"main.main\n\t/workspace/main.go:17\nruntime.main\n\t/usr/local/go/src/runtime/proc.go:271"}
Stream closed EOF for kong-system/kgo-gateway-operator-controller-manager-7549bd865b-vvzkt (manager)

Using the args provided in this PR users will be able to disable the controllers that require manual upgrade path (ControlPlane and Gateway), migrate to a newer KGO version, install new CRDs, and if they'd like enable those disabled controllers.