Handling edited messages + fixing protocolType() exception

Sometimes, when a verified BOT send a message to the host, after a time, the session starts to throw an exception, that says:

`java.lang.NullPointerException: Cannot invoke "it.auties.whatsapp.model.message.server.ProtocolMessage$Type.ordinal()" because the return value of "it.auties.whatsapp.model.message.server.ProtocolMessage.protocolType()" is null
	at it.auties.whatsapp.socket.MessageHandler.handleProtocolMessage(MessageHandler.java:934)
	at it.auties.whatsapp.socket.MessageHandler.saveMessage(MessageHandler.java:901)
	at it.auties.whatsapp.socket.MessageHandler.decodeChatMessage(MessageHandler.java:806)
	at it.auties.whatsapp.socket.MessageHandler.lambda$decode$55(MessageHandler.java:618)
	at java.base/java.lang.Iterable.forEach(Iterable.java:75)
	at it.auties.whatsapp.socket.MessageHandler.decode(MessageHandler.java:618)
	at it.auties.whatsapp.socket.SocketHandler.decodeMessage(SocketHandler.java:447)
	at it.auties.whatsapp.socket.StreamHandler.digest(StreamHandler.java:107)
	at it.auties.whatsapp.socket.SocketHandler.onMessage(SocketHandler.java:201)
	at it.auties.whatsapp.socket.SocketSession$WebSocketSession.notifyMessage(SocketSession.java:150)
	at it.auties.whatsapp.socket.SocketSession$WebSocketSession.onBinary(SocketSession.java:139)
	at it.auties.whatsapp.socket.SocketSession$WebSocketSession.onBinary(SocketSession.java:141)
	at it.auties.whatsapp.socket.SocketSession$WebSocketSession.onBinary(SocketSession.java:141)
`

src/main/java/it/auties/whatsapp/socket/MessageHandler.java

@@ -1076,10 +1076,12 @@ private void saveMessage(ChatMessageInfo info, boolean notify) {
             return;
         }
         if (info.message().hasCategory(MessageCategory.SERVER)) {
-            if (info.message().content() instanceof ProtocolMessage protocolMessage) {
+            if (!(info.message().content() instanceof ProtocolMessage protocolMessage)) return;
+            if (protocolMessage.protocolType() == null) return;
+            if (!protocolMessage.protocolType().equals(ProtocolMessage.Type.MESSAGE_EDIT)) {
                 handleProtocolMessage(info, protocolMessage);
+                return;
             }
-            return;
         }
 
         var chat = info.chat()