Update memberlist retransmit factor document

Signed-off-by: Alvin Lin <alvinlin@amazon.com>

pkg/ring/kv/memberlist/memberlist_client.go

@@ -170,7 +170,7 @@ func (cfg *KVConfig) RegisterFlags(f *flag.FlagSet, prefix string) {
 	f.StringVar(&cfg.NodeName, prefix+"memberlist.nodename", "", "Name of the node in memberlist cluster. Defaults to hostname.") // memberlist.DefaultLANConfig will put hostname here.
 	f.BoolVar(&cfg.RandomizeNodeName, prefix+"memberlist.randomize-node-name", true, "Add random suffix to the node name.")
 	f.DurationVar(&cfg.StreamTimeout, prefix+"memberlist.stream-timeout", 0, "The timeout for establishing a connection with a remote node, and for read/write operations. Uses memberlist LAN defaults if 0.")
-	f.IntVar(&cfg.RetransmitMult, prefix+"memberlist.retransmit-factor", 0, "Multiplication factor used when sending out messages (factor * log(N+1)).")
+	f.IntVar(&cfg.RetransmitMult, prefix+"memberlist.retransmit-factor", 0, "Multiplication factor used when sending out messages (factor * log(N+1)). Uses memberlist LAN defaults if 0.")
 	f.Var(&cfg.JoinMembers, prefix+"memberlist.join", "Other cluster members to join. Can be specified multiple times. It can be an IP, hostname or an entry specified in the DNS Service Discovery format (see https://cortexmetrics.io/docs/configuration/arguments/#dns-service-discovery for more details).")
 	f.DurationVar(&cfg.MinJoinBackoff, prefix+"memberlist.min-join-backoff", 1*time.Second, "Min backoff duration to join other cluster members.")
 	f.DurationVar(&cfg.MaxJoinBackoff, prefix+"memberlist.max-join-backoff", 1*time.Minute, "Max backoff duration to join other cluster members.")