#3805: Remove redundant PluginMessage handler in InitialHandler

There is no state in wich we could decode a PluginMessage in InitialHandler, so we should remove it here.

proxy/src/main/java/net/md_5/bungee/connection/InitialHandler.java

@@ -194,12 +194,6 @@ public class InitialHandler extends PacketHandler implements PendingConnection
         }
     }
 
-    @Override
-    public void handle(PluginMessage pluginMessage) throws Exception
-    {
-        this.relayMessage( pluginMessage );
-    }
-
     @Override
     public void handle(LegacyHandshake legacyHandshake) throws Exception
     {