Remove k8s dependency from BBR

[rramkumar1]

We get a rest config here:

https://github.com/kubernetes-sigs/gateway-api-inference-extension/blob/main/cmd/body-based-routing/main.go#L80

We shouldn't need to do this as BBR doesn't have any k8s dependency. This will likely require a slight rewrite of the server code too as we are reusing some k8s manager frameworks.