gRPC probes instead of Exec probes

[LionelJouin]

Is your feature request related to a problem? Please describe. Due to the ExecProbes, the userspaces program might be slower than expected. NFQLB in the stateless-lb might have some latency and performance issues.

We use Exec probes because the probes are exposed via GRPC, so we use this project for health checking: https://github.com/grpc-ecosystem/grpc-health-probe

Describe the solution you'd like Since Kubernetes 1.23, GRPC probes is a native feature, it can be enabled via the GRPCContainerProbe feature gate, and is already enabled from Kubernetes 1.24. We must replace all Exec probes by GRPC probes in all components for Kubernetes 1.24 deployment.

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Additional context /