Update our Network enum to include rust-bitcoin's Testnet4

Fixes lightningdevkit/ldk-garbagecollected#174

Author: TheBlueMatt

lightning-c-bindings/demo.cpp

@@ -564,7 +564,7 @@ int main() {
 	LDKThirtyTwoBytes chain_tip;
 	memset(&chain_tip, 0, sizeof(chain_tip)); // channel_open_header's prev_blockhash is all-0s
 
-	LDKNetwork network = LDKNetwork_Testnet;
+	LDKNetwork network = LDKNetwork_Testnet3;
 
 	// Trait implementations:
 	LDKBroadcasterInterface broadcast {

lightning-c-bindings/include/lightning.h

@@ -794,7 +794,11 @@ typedef enum LDKNetwork {
    /**
     * The testnet3 blockchain.
     */
-   LDKNetwork_Testnet,
+   LDKNetwork_Testnet3,
+   /**
+    * The testnet4 blockchain.
+    */
+   LDKNetwork_Testnet4,
    /**
     * A local test blockchain.
     */

lightning-c-bindings/src/bitcoin/network.rs

@@ -8,7 +8,9 @@ pub enum Network {
 	/// The main Bitcoin blockchain.
 	Bitcoin,
 	/// The testnet3 blockchain.
-	Testnet,
+	Testnet3,
+	/// The testnet4 blockchain.
+	Testnet4,
 	/// A local test blockchain.
 	Regtest,
 	/// A blockchain on which blocks are signed instead of mined.
@@ -19,15 +21,17 @@ impl Network {
 	pub(crate) fn into_bitcoin(&self) -> BitcoinNetwork {
 		match self {
 			Network::Bitcoin => BitcoinNetwork::Bitcoin,
-			Network::Testnet => BitcoinNetwork::Testnet,
+			Network::Testnet3 => BitcoinNetwork::Testnet,
+			Network::Testnet4 => BitcoinNetwork::Testnet4,
 			Network::Regtest => BitcoinNetwork::Regtest,
 			Network::Signet => BitcoinNetwork::Signet,
 		}
 	}
 	pub(crate) fn from_bitcoin(net: &BitcoinNetwork) -> Self {
 		match net {
 			BitcoinNetwork::Bitcoin => Network::Bitcoin,
-			BitcoinNetwork::Testnet => Network::Testnet,
+			BitcoinNetwork::Testnet => Network::Testnet3,
+			BitcoinNetwork::Testnet4 => Network::Testnet4,
 			BitcoinNetwork::Regtest => Network::Regtest,
 			BitcoinNetwork::Signet => Network::Signet,
 			_ => unreachable!(),