#770: Send messages without sender with SYSTEM type again

This was the behaviour before the 1.16 update and made it so that any
 message sent by a plugin was treated as a system message allowing the
 player to disable chat messages while keeping access to commands.

After 1.16 disabling the chat also disabled any plugin output, this
 restores the original behaviour.

By: Phoenix616 <max@themoep.de>

paper-server/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -195,7 +195,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         if (getHandle().playerConnection == null) return;
 
         for (IChatBaseComponent component : CraftChatMessage.fromString(message)) {
-            getHandle().playerConnection.sendPacket(new PacketPlayOutChat(component, ChatMessageType.CHAT, SystemUtils.b));
+            getHandle().playerConnection.sendPacket(new PacketPlayOutChat(component, ChatMessageType.SYSTEM, SystemUtils.b));
         }
     }