New Objective: Ensure another traitor stays alive. (#6020)

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>
Co-authored-by: metalgearsloth <comedian_vs_clown@hotmail.com>

Content.Server/GameTicking/Rules/TraitorRuleSystem.cs

@@ -41,6 +41,8 @@ public class TraitorRuleSystem : GameRuleSystem
     private readonly List<TraitorRole> _traitors = new ();
 
     private const string TraitorPrototypeID = "Traitor";
+    
+    public int TotalTraitors => _traitors.Count;
 
     public override void Initialize()
     {