Mark as not listening when stopping

Author: dsmurfin

Sources/sACNKit/Receiver/sACNDiscoveryReceiver.swift

@@ -174,7 +174,8 @@ public class sACNDiscoveryReceiver {
     public func stop() {
         socketDelegateQueue.sync {
             guard _isListening else { return }
-
+            _isListening = false
+            
             stopHeartbeat()
 
             sockets.forEach { interface, socket in

Sources/sACNKit/Receiver/sACNReceiverRaw.swift

@@ -235,7 +235,8 @@ public class sACNReceiverRaw {
     public func stop() {
         socketDelegateQueue.sync {
             guard _isListening else { return }
-
+            self._isListening = false
+            
             sampleTimer = nil
             stopHeartbeat()
 

Sources/sACNKit/Source/sACNSource.swift

@@ -246,6 +246,7 @@ final public class sACNSource {
     public func stop() {
         socketDelegateQueue.sync {
             guard _isListening else { return }
+            self._isListening = false
 
             // stops heartbeats
             stopUniverseDiscovery()