Remove global server reference from Player_antiCheatDisabledMixin

src/main/java/carpet/mixins/Player_antiCheatDisabledMixin.java

@@ -1,7 +1,7 @@
 package carpet.mixins;
 
-import carpet.CarpetServer;
 import carpet.CarpetSettings;
+import net.minecraft.server.level.ServerPlayer;
 import net.minecraft.world.entity.EquipmentSlot;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.item.ElytraItem;
@@ -23,7 +23,7 @@ public abstract class Player_antiCheatDisabledMixin
     @Inject(method = "tryToStartFallFlying", at = @At("HEAD"), cancellable = true)
     private void allowDeploys(CallbackInfoReturnable<Boolean> cir)
     {
-        if (CarpetSettings.antiCheatDisabled && CarpetServer.minecraft_server != null && CarpetServer.minecraft_server.isDedicatedServer())
+        if (CarpetSettings.antiCheatDisabled && (Object)this instanceof ServerPlayer sp && sp.getServer().isDedicatedServer())
         {
             ItemStack itemStack_1 = getItemBySlot(EquipmentSlot.CHEST);
             if (itemStack_1.getItem() == Items.ELYTRA && ElytraItem.isFlyEnabled(itemStack_1)) {