Disable the etcd3 client logger

This logger is responsible for 20% of the API server's memory usage when
many CRDs are installed. See the below issue for more context.

https://github.com/kubernetes/kubernetes/issues/111476

Signed-off-by: Nic Cope <nicc@rk0n.org>

Kubernetes-commit: 0e5401c93940126beac45264aa056507b0950075

pkg/storage/storagebackend/factory/etcd3.go

@@ -30,6 +30,7 @@ import (
 	"go.etcd.io/etcd/client/pkg/v3/transport"
 	clientv3 "go.etcd.io/etcd/client/v3"
 	"go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
+	"go.uber.org/zap"
 	"google.golang.org/grpc"
 
 	"k8s.io/apimachinery/pkg/runtime"
@@ -223,6 +224,10 @@ var newETCD3Client = func(c storagebackend.TransportConfig) (*clientv3.Client, e
 		DialOptions:          dialOptions,
 		Endpoints:            c.ServerList,
 		TLS:                  tlsConfig,
+
+		// This logger uses a significant amount of memory when many CRDs (i.e.
+		// 1,000+) are added to the API server, so we disable it.
+		Logger: zap.NewNop(),
 	}
 
 	return clientv3.New(cfg)