Set timeout to 0

Since it seems like the timeout is ignored (maybe because of the dispatcher
somehow?).

src/commonTest/kotlin/fr/acinq/lightning/blockchain/electrum/ElectrumClientTest.kt

@@ -149,7 +149,7 @@ class ElectrumClientTest : LightningTestSuite() {
     fun `disconnect from slow servers on subscription attempts`() = runTest { client ->
         // Set a very small timeout that the server won't be able to honor.
         println("${Clock.System.now()} - setting low RPC timeout")
-        client.setRpcTimeout(1.milliseconds)
+        client.setRpcTimeout(0.milliseconds)
         val subscriptionJob = async { client.startHeaderSubscription() }
         // We automatically disconnect after timing out on the subscription request.
         client.connectionStatus.first { it is ElectrumConnectionStatus.Closed }