Fix review comments and new changes in config (#8515)

- Migrate and save only settings which are enabled
- Rename logger_http to logger_webhook and
  logger_http_audit to audit_webhook
- No more pretty printing comments, comment
  is a key=value pair now.
- Avoid quotes on values which do not have space in them
- `state="on"` is implicit for all SetConfigKV unless
  specified explicitly as `state="off"`
- Disabled IAM users should be disabled always

pkg/event/target/nats.go

@@ -43,7 +43,7 @@ const (
 	NATSQueueLimit   = "queue_limit"
 
 	// Streaming constants
-	NATSStreamingEnable             = "streaming_enable"
+	NATSStreaming                   = "streaming"
 	NATSStreamingClusterID          = "streaming_cluster_id"
 	NATSStreamingAsync              = "streaming_async"
 	NATSStreamingMaxPubAcksInFlight = "streaming_max_pub_acks_in_flight"
@@ -60,7 +60,7 @@ const (
 	EnvNATSQueueLimit   = "MINIO_NOTIFY_NATS_QUEUE_LIMIT"
 
 	// Streaming constants
-	EnvNATSStreamingEnable             = "MINIO_NOTIFY_NATS_STREAMING_ENABLE"
+	EnvNATSStreaming                   = "MINIO_NOTIFY_NATS_STREAMING"
 	EnvNATSStreamingClusterID          = "MINIO_NOTIFY_NATS_STREAMING_CLUSTER_ID"
 	EnvNATSStreamingAsync              = "MINIO_NOTIFY_NATS_STREAMING_ASYNC"
 	EnvNATSStreamingMaxPubAcksInFlight = "MINIO_NOTIFY_NATS_STREAMING_MAX_PUB_ACKS_IN_FLIGHT"