Fix demo flag not enabling demo mode (#9103)

patches/server/0974-Fix-demo-flag-not-enabling-demo-mode.patch

@@ -0,0 +1,20 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Warrior <50800980+Warriorrrr@users.noreply.github.com>
+Date: Fri, 7 Apr 2023 20:11:17 +0200
+Subject: [PATCH] Fix demo flag not enabling demo mode
+
+https://github.com/PaperMC/Paper/issues/9046
+
+diff --git a/src/main/java/net/minecraft/server/Main.java b/src/main/java/net/minecraft/server/Main.java
+index c6fa6bcd66d61359124a8426b919493c6ec43f06..cdbf10339a8e8846a8c364de483a0ccd95cd225a 100644
+--- a/src/main/java/net/minecraft/server/Main.java
++++ b/src/main/java/net/minecraft/server/Main.java
+@@ -301,7 +301,7 @@ public class Main {
+                 /*
+                 dedicatedserver1.setSingleplayerProfile(optionset.has(optionspec8) ? new GameProfile((UUID) null, (String) optionset.valueOf(optionspec8)) : null);
+                 dedicatedserver1.setPort((Integer) optionset.valueOf(optionspec11));
+-                dedicatedserver1.setDemo(optionset.has(optionspec2));
++                */dedicatedserver1.setDemo(optionset.has("demo"));/* // Paper - Restore setting the demo mode
+                 dedicatedserver1.setId((String) optionset.valueOf(optionspec12));
+                 */
+                 boolean flag1 = !optionset.has("nogui") && !optionset.nonOptionArguments().contains("nogui");