fix: readiness needs to be like liveness (#9941)

Readiness as no reasoning to be cluster scope
because that is not how the k8s networking works
for pods, all the pods to a deployment are not
sharing the network in a singleton. Instead they
are run as local scopes to themselves, with
readiness failures the pod is potentially taken
out of the network to be resolvable - this
affects the distributed setup in myriad of
different ways.

Instead readiness should behave like liveness
with local scope alone, and should be a dummy
implementation.

This PR all the startup times and overal k8s
startup time dramatically improves.

Added another handler called as `/minio/health/cluster`
to understand the cluster scope health.

cmd/endpoint.go

@@ -44,8 +44,6 @@ const (
 
 	// URLEndpointType - URL style endpoint type enum.
 	URLEndpointType
-
-	retryInterval = 5 // In Seconds.
 )
 
 // Endpoint - any type of endpoint.
@@ -302,7 +300,7 @@ func (endpoints Endpoints) UpdateIsLocal(foundPrevLocal bool) error {
 	resolvedList := make([]bool, len(endpoints))
 	// Mark the starting time
 	startTime := time.Now()
-	keepAliveTicker := time.NewTicker(retryInterval * time.Second)
+	keepAliveTicker := time.NewTicker(10 * time.Millisecond)
 	defer keepAliveTicker.Stop()
 	for {
 		// Break if the local endpoint is found already Or all the endpoints are resolved.