Avoid notification event for replicas (#11683)

Creating notification events for replica creation
is not particularly useful to send as the notification
event generated at source already includes replication
completion events.

For applications using replica cluster as failover, avoiding
duplicate notifications for replica event will allow seamless
failover.

cmd/handler-utils.go

@@ -234,12 +234,16 @@ func extractReqParams(r *http.Request) map[string]string {
 	cred := getReqAccessCred(r, region)
 
 	// Success.
-	return map[string]string{
+	m := map[string]string{
 		"region":          region,
 		"accessKey":       cred.AccessKey,
 		"sourceIPAddress": handlers.GetSourceIP(r),
 		// Add more fields here.
 	}
+	if _, ok := r.Header[xhttp.MinIOSourceReplicationRequest]; ok {
+		m[xhttp.MinIOSourceReplicationRequest] = ""
+	}
+	return m
 }
 
 // Extract response elements to be sent with event notifiation.