Fix shard sort order when deciding if a mana cost is payable.

Prior to this change, the logic would conclude that a {1}{W} cost is not payable with an untapped Scoured Barrens (w/b) and Jungle Hollow (b/g) on the field.

The code is unfortunately too tangled (has too many dependencies) to write a unit test for this. Ideally, we should refactor so it wouldn't depend on the player, etc and just take parameters that can be fed test data.

forge-ai/src/main/java/forge/ai/ComputerUtilMana.java

@@ -697,11 +697,7 @@ public class ComputerUtilMana {
         // * pay hybrids
         // * pay phyrexian, keep mana for colorless
         // * pay colorless
-        Iterator<ManaCostShard> shards = cost.getDistinctShards().iterator();
-        if (shards.hasNext()) {
-            return shards.next();
-        }
-        return null;
+        return cost.getShardToPayByPriority(cost.getDistinctShards(), MagicColor.ALL_COLORS);
     }
 
     private static void adjustManaCostToAvoidNegEffects(ManaCostBeingPaid cost, final Card card, Player ai) {