Fix demo flag not enabling demo mode

https://github.com/PaperMC/Paper/issues/9046

paper-server/patches/sources/net/minecraft/server/Main.java.patch

@@ -217,7 +217,7 @@
                                  worlddimensions = dedicatedserverproperties.createDimensions(worldloader_a.datapackWorldgen());
                              }
  
-@@ -225,32 +308,45 @@
+@@ -225,32 +308,47 @@
                  return;
              }
  
@@ -244,7 +244,10 @@
  
 +                /*
                  dedicatedserver1.setPort((Integer) optionset.valueOf(optionspec11));
-                 dedicatedserver1.setDemo(optionset.has(optionspec2));
+-                dedicatedserver1.setDemo(optionset.has(optionspec2));
++                */
++                dedicatedserver1.setDemo(optionset.has("demo")); // Paper
++                /*
                  dedicatedserver1.setId((String) optionset.valueOf(optionspec12));
 -                boolean flag2 = !optionset.has(optionspec) && !optionset.valuesOf(optionspec15).contains("nogui");
 +                */
@@ -268,7 +271,7 @@
              Thread thread = new Thread("Server Shutdown Thread") {
                  public void run() {
                      dedicatedserver.halt(true);
-@@ -259,6 +355,7 @@
+@@ -259,6 +357,7 @@
  
              thread.setUncaughtExceptionHandler(new DefaultUncaughtExceptionHandler(Main.LOGGER));
              Runtime.getRuntime().addShutdownHook(thread);
@@ -276,7 +279,7 @@
          } catch (Exception exception1) {
              Main.LOGGER.error(LogUtils.FATAL_MARKER, "Failed to start the minecraft server", exception1);
          }
-@@ -295,7 +392,7 @@
+@@ -295,7 +394,7 @@
      }
  
      public static void forceUpgrade(LevelStorageSource.LevelStorageAccess session, DataFixer dataFixer, boolean eraseCache, BooleanSupplier continueCheck, RegistryAccess dynamicRegistryManager, boolean recreateRegionFiles) {