config: add testnet4 network option

Author: bitcoin-coder-bob

config.go

@@ -180,7 +180,7 @@ type Config struct {
 	// before the configuration is loaded and will set the correct flag on
 	// `lnd.bitcoin.mainnet|testnet|regtest|signet` and also for the other
 	// daemons. That way only one global network flag is needed.
-	Network string `long:"network" description:"The network the UI and all its components run on" choice:"regtest" choice:"testnet" choice:"mainnet" choice:"simnet" choice:"signet"`
+	Network string `long:"network" description:"The network the UI and all its components run on" choice:"regtest" choice:"testnet" choice:"testnet4" choice:"mainnet" choice:"simnet" choice:"signet"`
 
 	Remote *subservers.RemoteConfig `group:"Remote mode options (use when lnd-mode=remote)" namespace:"remote"`
 
@@ -810,6 +810,9 @@ func setNetwork(cfg *Config) error {
 	case "testnet", "testnet3":
 		cfg.Lnd.Bitcoin.TestNet3 = true
 
+	case "testnet4":
+		cfg.Lnd.Bitcoin.TestNet4 = true
+
 	case "regtest":
 		cfg.Lnd.Bitcoin.RegTest = true