Remove superfluous addManaCost method (#11288)

* no need to specify mana cost, just add cost

* handle all mana costs through addcost method only

* eliminate another constructor

* more constructor cleanup

Mage/src/main/java/mage/abilities/keyword/SuspendAbility.java

@@ -132,7 +132,7 @@ public class SuspendAbility extends SpecialAction {
         if (suspend == Integer.MAX_VALUE) {
             VariableManaCost xCosts = new VariableManaCost(VariableCostType.ALTERNATIVE);
             xCosts.setMinX(1);
-            this.addManaCost(xCosts);
+            this.addCost(xCosts);
             cost = new ManaCostsImpl<>("{X}" + cost.getText());
         }
         StringBuilder sb = new StringBuilder("Suspend ");