Unlock utxos when peer is unavailable for splice (#564)

If the peer is offline when the swap-in job requests a splice-in, the
request will be ignored, but we weren't unlocking UTXOs, preventing any
further attempt.

src/commonMain/kotlin/fr/acinq/lightning/io/Peer.kt

@@ -1076,6 +1076,7 @@ class Peer(
                         } else {
                             // There are existing channels but not immediately usable (e.g. creating, disconnected), we don't do anything yet
                             logger.info { "ignoring channel request, existing channels are not ready for splice-in: ${channels.values.map { it::class.simpleName }}" }
+                            swapInCommands.trySend(SwapInCommand.UnlockWalletInputs(cmd.walletInputs.map { it.outPoint }.toSet()))
                         }
                     }
                 }