Fixes crash when player in CREATIVE shift+clicks on INVENTORY challenge.

Limit completion time to 2, if player is in creative instead of Integer.MAX_VALUE

Fixes #330

src/main/java/world/bentobox/challenges/tasks/TryToComplete.java

@@ -952,6 +952,8 @@ public class TryToComplete
         else
         {
             requiredItems = Collections.emptyList();
+            // Set maxTime to 2, to not crash client when completing 2147483647 times.
+            maxTimes = 2;
         }
 
         // Return the result